February 28, 2024 - 10-K: Annual report pursuant to Section 13 and 15(d)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2023

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission file number: 001-37351

National Storage Affiliates Trust

(Exact name of Registrant as specified in its charter)


Maryland						46-5053858
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)

8400 East Prentice Avenue, 9th Floor

Greenwood Village, Colorado 80111

(Address of principal executive offices) (Zip code)

(720) 630-2600

(Registrant's telephone number including area code)

Securities registered pursuant to Section 12(b) of the Act:


Title of each class	Trading symbols	Name of each exchange on which registered
Common Shares of Beneficial Interest, $0.01 par value per share	NSA	New York Stock Exchange
Series A Cumulative Redeemable Preferred Shares of Beneficial Interest, par value $0.01 per share	NSA Pr A	New York Stock Exchange
Series B Cumulative Redeemable Preferred Shares of Beneficial Interest, par value $0.01 per share	NSA Pr B	New York Stock Exchange

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large Accelerated Filer

☒

Accelerated Filer

☐

Non-accelerated Filer

☐

Smaller Reporting Company

☐

Emerging Growth Company

☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to § 240.10D-1(b). ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting common shares of beneficial interest of National Storage Affiliates Trust held by non-affiliates of National Storage Affiliates Trust was approximately $3.1 billion as of June 30, 2023. As of February 26, 2024, 79,977,268 common shares of beneficial interest, $0.01 par value per share, were outstanding.



Documents Incorporated by Reference

Portions of the registrant's definitive proxy statement for its annual meeting of shareholders are incorporated by reference into Part III of this Annual Report on Form 10-K.

Auditor Name:

KPMG LLP

Auditor Location:

Denver, Colorado

Auditor Firm ID:

185


NATIONAL STORAGE AFFILIATES TRUST

TABLE OF CONTENTS

ANNUAL REPORT ON FORM 10-K
	For the Fiscal Year Ended December 31, 2023
Item		Page
PART I
1.	Business	4
1A.	Risk Factors	16
1B.	Unresolved Staff Comments	30
1C.	Cybersecurity	30
2.	Properties	32
3.	Legal Proceedings	34
4.	Mine Safety Disclosures	34

PART II
5.	Market for the Registrant's Common Equity, Related Shareholder Matters and Issuer Purchases of Equity Securities	35
6.	Selected Financial Data	37
7.	Management's Discussion and Analysis of Financial Condition and Results of Operations	38
7A.	Quantitative and Qualitative Disclosures About Market Risk	58
8.	Financial Statements and Supplementary Data	58
9.	Changes in and Disagreements With Accountants on Accounting and Financial Disclosure	58
9A.	Controls and Procedures	58
9B.	Other Information	59

PART III
10.	Directors, Executive Officers and Corporate Governance	59
11.	Executive Compensation	59
12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	59
13.	Certain Relationships and Related Transactions, and Director Independence	60
14.	Principal Accounting Fees and Services	60

PART IV
15.	Exhibits and Financial Statement Schedules	60
16.	Form 10-K Summary	63

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FORWARD-LOOKING STATEMENTS

National Storage Affiliates Trust and its consolidated subsidiaries (the "Company", "NSA," "we," "our", and "us") make forward-looking statements in this report that are subject to risks and uncertainties. These forward-looking statements include information about possible or assumed future results of our business, financial condition, liquidity, results of operations, plans and objectives. When we use the words "believe," "expect," "anticipate," "estimate," "plan," "continue," "intend," "should," "may," or similar expressions, we intend to identify forward-looking statements.

The forward-looking statements contained in this report reflect our current views about future events and are subject to numerous known and unknown risks, uncertainties, assumptions, and changes in circumstances that may cause our actual results to differ significantly from those expressed in any forward-looking statement.

Statements regarding the following subjects, among others, may be forward-looking:

•market trends in our industry, interest rates, inflation, the debt and lending markets or the general economy;

•our business and investment strategy;

•the acquisition or disposition of properties, including those under contract, and the ability of our acquisitions to achieve underwritten capitalization rates and our ability to execute on our acquisition pipeline;

•the internalization of retiring participating regional operators ("PROs") into the Company;

•the timing of acquisitions or dispositions;

•our relationships with, and our ability and timing to attract additional, PROs;

•our ability to effectively align the interests of our PROs with us and our shareholders;

•the integration of our PROs and their managed portfolios into the Company, including into our financial and operational reporting infrastructure and internal control framework;

•our operating performance and projected operating results, including our ability to achieve market rents and occupancy levels, reduce operating expenditures and increase the sale of ancillary products and services;

•our ability to access additional off-market acquisitions;

•actions and initiatives of the U.S. federal, state and local government and changes to U.S. federal, state and local government policies, regulations, tax laws and rates (and related accounting guidance), and the execution and impact of these actions, initiatives, policies, regulations and laws;

•the state of the U.S. economy generally or in specific geographic regions, states, territories or municipalities;

•economic trends and economic recoveries;

•our ability to obtain and maintain financing arrangements on favorable terms;

•general volatility of the securities markets in which we participate;

•impacts from highly infectious or contagious diseases, including unfavorable changes to economic conditions that could adversely affect occupancy levels, rental rates, expenses and the ability of the Company's tenants to pay rent;

•changes in the value of our assets;

•projected capital expenditures;

•the impact of technology on our products, operations, and business;

•the implementation of our technology and best practices programs (including our ability to effectively implement our integrated Internet marketing strategy);

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•changes in interest rates, the degree to which our hedging strategies may or may not protect us from interest rate volatility and the impact of such changes on the economy and our industry;

•our ability to continue to qualify and maintain our qualification as a real estate investment trust for U.S. federal income tax purposes ("REIT");

•availability of qualified personnel;

•the timing of conversions of each series of Class B common units of limited partner interest ("subordinated performance units") in NSA OP, LP (our "operating partnership") and subsidiaries of our operating partnership into Class A common units of limited partner interest ("OP units") in our operating partnership, the conversion ratio in effect at such time and the impact of such convertibility on our diluted earnings (loss) per share;

•the risks of investing through joint ventures, including whether the anticipated benefits from a joint venture are realized or may take longer to realize than expected;

•risks related to or a consequence of natural disasters or acts of violence, pandemics, active shooters, terrorism, insurrection or war that affect the markets in which we operate;

•estimates relating to our ability to make distributions to our shareholders in the future; and

•our understanding of our competition.

The forward-looking statements are based on our beliefs, assumptions and expectations of our future performance, taking into account all information currently available to us. Forward-looking statements are not predictions of future events. These beliefs, assumptions, and expectations can change as a result of many possible events or factors, not all of which are known to us. Readers should carefully review our financial statements and the notes thereto, as well as the sections entitled "Business," "Risk Factors," "Properties," and "Management's Discussion and Analysis of Financial Condition and Results of Operations," described in Item 1, Item 1A, Item 2 and Item 7, respectively, of this Annual Report on Form 10-K and the other documents we file from time to time with the Securities and Exchange Commission. If a change occurs, our business, financial condition, liquidity and results of operations may vary materially from those expressed in our forward-looking statements. Any forward-looking statement speaks only as of the date on which it is made. New risks and uncertainties arise over time, and it is not possible for us to predict those events or how they may affect us. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Except as required by law, we are not obligated to, and do not intend to, update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

PART I

Item 1. Business

General

National Storage Affiliates Trust is a fully integrated, self-administered and self-managed real estate investment trust organized in the state of Maryland on May 16, 2013. We have elected and we believe that we have qualified to be taxed as a REIT for U.S. federal income tax purposes commencing with our taxable year ended December 31, 2015. We serve as the sole general partner of our operating partnership subsidiary, NSA OP, LP (our "operating partnership"), a Delaware limited partnership formed on February 13, 2013 to conduct our business, which is focused on the ownership, operation, and acquisition of self storage properties predominantly located within the top 100 metropolitan statistical areas ("MSAs") throughout the United States. As of December 31, 2023, we held ownership interests in and operated a geographically diversified portfolio of 1,050 self storage properties located in 42 states and Puerto Rico, comprising approximately 68.6 million rentable square feet, configured in approximately 542,000 storage units, which excludes 39 self storage properties classified as held for sale to be sold to a third party in 2024. We completed our initial public offering in 2015 and our common shares of beneficial interest, $0.01 par value per share ("common shares"), are listed on the New York Stock Exchange under the symbol "NSA."

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Our vice chairperson of the board of trustees and former chief executive officer, Arlen D. Nordhagen, co-founded SecurCare Self Storage, Inc. ("SecurCare"), in 1988 to invest in and manage self storage properties. While growing SecurCare to over 150 self storage properties, Mr. Nordhagen recognized a market opportunity for a differentiated public self storage REIT that would leverage the benefits of national scale by integrating multiple experienced regional self storage operators with local operational focus and expertise. We believe that his vision, which is the foundation of the Company, aligns the interests of our participating regional operators ("PROs"), with those of our public shareholders by allowing our PROs to participate alongside our shareholders in our financial performance and the performance of our PROs' "managed portfolios", which means, with respect to each PRO, the portfolio of properties that such PRO manages on our behalf. A key component of this strategy is to capitalize on the local market expertise and knowledge of regional self storage operators by maintaining the continuity of their roles as property managers.

As of December 31, 2023, our PROs managed 333 of our properties. We believe that our PRO structure creates the right financial incentives to align the interest of our PROs with those of our public shareholders. We require our PROs to exchange the self storage properties they contribute to the Company for a combination of OP units and subordinated performance units in our operating partnership or subsidiaries of our operating partnership that issue units intended to be economically equivalent to the OP units and subordinated performance units issued by our operating partnership ("DownREIT partnerships"). OP units, which are economically equivalent to our common shares, create alignment with the performance of the Company as a whole. Subordinated performance units, which are linked to the performance of specific managed portfolios, incentivize our PROs to drive operating performance and support the sustainability of the operating cash flow generated by the self storage properties that they manage on our behalf. Because subordinated performance unit holders receive distributions only after portfolio-specific minimum performance thresholds are satisfied, subordinated performance units play a key role in aligning the interests of our PROs with us and our shareholders. Our PRO structure thus offers PROs a unique opportunity to serve as regional property managers for their managed portfolios and directly participate in the potential upside of those properties while simultaneously diversifying their investment to include a broader portfolio of self storage properties. We believe our PRO structure provides us with a competitive growth advantage over self storage companies that do not offer property owners the ability to participate in the performance and potential future growth of their managed portfolios.

We believe that our national platform, which includes our PRO structure and property management platform, has significant potential for continued external and internal growth. We seek to further expand our national platform by continuing to recruit additional established self storage operators to act as future PROs, pursuing strategic off-market acquisitions, as well as opportunistically partnering with institutional funds and other institutional investors in strategic joint venture arrangements while integrating our operations through the implementation of centralized initiatives, including management information systems, revenue enhancement, and cost optimization programs. We are currently engaged in preliminary discussions with additional self storage operators and believe that we could add one to three more PROs in addition to the PROs we have currently, which will enhance our existing geographic footprint and allow us to enter regional markets in which we currently have limited or no market share.

At the time of our formation, we contemplated that PROs would seek to retire over time, allowing us to internalize the management of such PROs' managed portfolios into our full service internally staffed property management platform, which was initially developed to manage the properties owned by our unconsolidated real estate ventures. Internalization allows us to grow this platform by hiring former PRO employees to continue managing the same portfolios under the same local brands. With each retirement event, we acquire the PRO brand name and related intellectual property and discontinue paying the PRO supervisory and administrative fees and reimbursements. As of December 31, 2023, we have completed three retirement events: SecurCare effective March 31, 2020, Kevin Howard Real Estate, Inc., d/b/a Northwest Self Storage and its controlled affiliates ("Northwest") effective January 1, 2022 and Move It Self Storage and its controlled affiliates ("Move It") effective January 1, 2023.

As a result of Move It's retirement, effective January 1, 2023, management of our properties in the Move It managed portfolio was transferred to us and the Move It brand name and related intellectual property was internalized by us, and we discontinued payment of any supervisory and administrative fees and reimbursements to Move It.

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Our Property Management Platform

Through our property management platform, we direct, manage and control the day-to-day operations and affairs of certain consolidated properties and our unconsolidated real estate ventures under our iStorage, SecurCare, Northwest and Move It brands. As of December 31, 2023, our property management platform managed and controlled 532 of our consolidated properties, which excludes 39 properties classified as held for sale to be sold to a third party in 2024, and 185 of our unconsolidated real estate venture properties.

We earn certain customary fees for managing and operating the properties in the unconsolidated real estate ventures and we facilitate tenant insurance and/or tenant warranty protection programs for tenants at these properties in exchange for half of all proceeds from such programs.

Our PROs

The Company had eight PROs as of December 31, 2023: Optivest Properties LLC and its controlled affiliates ("Optivest"), Guardian Storage Centers LLC and its controlled affiliates ("Guardian"), Southern Storage Management Systems, Inc. d/b/a Southern Self Storage ("Southern"), Blue Sky Self Storage LLC, a strategic partnership between Argus Professional Storage Management and Uplift Development Group (formerly known as GYS Development LLC) ("Blue Sky"), affiliates of Investment Real Estate Management, LLC d/b/a Moove In Self Storage ("Moove In"), Hide-Away Storage Services, Inc. and its controlled affiliates ("Hide-Away"), Arizona Mini Storage Management Company d/b/a Storage Solutions and its controlled affiliates ("Storage Solutions"), and an affiliate of Shader Brothers Corporation d/b/a Personal Mini Storage ("Personal Mini").

To capitalize on their recognized and established local brands, our PROs continue to function as property managers for their managed portfolios under their existing brands (which include various brands in addition to those discussed below). Over the long-run, we may seek to continue internalizing our PROs and may brand or co-brand each location as part of NSA.

•Optivest, which is based in Dana Point, California, is one of our PROs responsible for covering portions of the northeast and southwest regions. Optivest managed 86 of our properties located in Arizona, California, Massachusetts, Nevada, New Hampshire, New Mexico, Texas and Utah as of December 31, 2023. Optivest is run by its co-founder, Warren Allan, who has more than 30 years of financial and operational management experience in the self storage industry and is recognized as a self storage acquisition and development specialist.

•Guardian, which is based in Irvine, California, is one of our PROs responsible for covering portions of the southern California and southwest regions. Guardian managed 58 of our properties located in Arizona, California and Nevada as of December 31, 2023. Guardian is led by John Minar, who has more than 40 years of self storage acquisition, rehabilitation, ownership, operations and development experience.

•Southern, which is based in Palm Beach Gardens, Florida, is one of our PROs responsible for covering portions of Arizona, New Mexico and the southeast region, including New Orleans, the Florida Panhandle, southern Georgia and Puerto Rico. Southern managed 49 of our properties in Arizona, Louisiana, the Florida Panhandle, New Mexico, southern Georgia, and Puerto Rico as of December 31, 2023. Southern is led by Bob McIntosh and Peter Cowie, who are active real estate operators with more than 40 years of self storage experience.

•Blue Sky, which is a strategic partnership between Argus Professional Storage Management and Uplift Development Group (formerly known as GYS Development LLC) and is based in the mountain west, is our PRO responsible for covering portions of the southeast, midwest, and southwest regions, including portions of Kansas, Georgia and Texas. Blue Sky managed 41 of our properties in Alabama, Arkansas, Colorado, Florida, Georgia, Indiana, Kansas, Kentucky, Minnesota, Montana, North Carolina, Texas, Wisconsin and Wyoming as of December 31, 2023. Blue Sky is led by Lee Fredrick, Ben Vestal and Michael Perry, who have extensive experience in acquisition, development and management of self storage properties.

•Moove In, which is based in York, Pennsylvania, is our PRO responsible for covering portions of the mid-atlantic and midwest regions. Moove In managed 38 of our properties in Connecticut, Iowa, Maryland, Massachusetts, New Jersey, New York and Pennsylvania as of December 31, 2023. Moove In is led by John Gilliland, who currently serves on the board of directors for the Large Owners Council of the Self Storage Association, and a past Chairman of the Self Storage Association.

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•Hide-Away, which is based in Sarasota, Florida, is our PRO responsible for covering the western Florida market. Hide-Away managed 25 of our properties in western Florida as of December 31, 2023. Hide-Away is led by its founder, Steve Wilson, one of the early developers of the self storage business, who served for more than 40 years as the President of Hide-Away and its related entities, and is a past Chairman of the Self Storage Association.

•Personal Mini, which is based in Orlando, Florida, is our PRO responsible for covering portions of the central Florida market. Personal Mini managed 25 of our properties in central Florida as of December 31, 2023. Personal Mini is led by Marc Smith, a self storage investor who has been involved in all facets of the self storage business. Mr. Smith is a past Chairman of the Self Storage Association, and also previously served as president of the Southeast Region of the Self Storage Association.

•Storage Solutions, which is based in Chandler, Arizona, is our PRO responsible for covering portions of the Arizona and Nevada markets. Storage Solutions managed 11 of our properties in Arizona and Nevada as of December 31, 2023. Storage Solutions is led by its founder, Bill Bohannan, who is one of the largest operators in Phoenix and has more than 40 years of self storage acquisition, development and management experience. Mr. Bohannan is recognized in the industry as a self storage acquisition, development and management specialist.

We benefit from the local market knowledge and active presence of our PROs, allowing us to build and foster important customer and industry relationships. These local relationships provide attractive off-market acquisition opportunities that we believe will continue to fuel additional external growth.

We believe our structure allows our PROs to optimize their established property management platforms while addressing financial and operational hurdles. Before joining us, our PROs faced challenges in securing low cost capital and had to manage multiple investors and lending relationships, making it difficult to compete with larger competitors, including public REITs, for acquisition and investment opportunities. Our PROs were also limited in their ability to raise growth capital through the sale of assets, a portfolio refinancing, or capital contributions from new equity partners. Serving as our on-the-ground acquisition teams, our PROs now have access to our broader financing sources and lower cost of capital, while our national platform allows them to benefit from economies of scale to drive operating efficiencies in a rapidly evolving, technology-driven industry.

Our Consolidated Properties

We seek to own properties that are well located in high quality sub-markets with highly accessible street access and attractive supply and demand characteristics, providing our properties with strong and stable cash flows that we believe are less sensitive to the fluctuations of the general economy. Many of these markets have multiple barriers to entry against increased supply, including zoning restrictions against new construction and new construction costs that we believe are higher than our properties' fair market value. As of December 31, 2023, we owned a geographically diversified portfolio of 809 self storage properties located in 38 states and Puerto Rico, comprising approximately 51.9 million rentable square feet, configured in approximately 407,000 storage units, which excludes self storage properties classified as held for sale consisting of (i) 39 self storage properties located in eight states, comprising approximately 2.4 million rentable square feet, configured in approximately 18,000 storage units to be sold to a third party in 2024 and (ii) 56 self storage properties located in seven states, comprising approximately 3.2 million rentable square feet, configured in approximately 24,000 storage units that were contributed to the 2024 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8) in 2024. Of these properties, 306 were acquired by us from our PROs, 502 were acquired by us from third-party sellers and one was acquired by us from the 2016 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8). A complete listing of, and additional information about, our self storage properties is included in Item 2 of this report.

During the year ended December 31, 2023, we acquired 20 consolidated self storage properties and annexes to existing properties, of which 19 were acquired by us from our PROs and one was acquired by us from a third-party seller. The following is a summary of our 2023 consolidated acquisition activity (dollars in thousands):

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	Number of	Number of	Rentable
State/Territory	Properties	Units	Square Feet	Fair Value
2023 Acquisitions:
Florida	15	7,388	905,157	$	144,355
California(1)	1	1,038	140,947	28,291
Texas	1	502	67,000	8,406
Arizona	1	489	54,885	16,181
Nevada	1	460	61,856	12,213
Puerto Rico	1	443	46,069	16,180
Georgia(1)	—	159	22,950	3,237
Louisiana(2)	—	—	—	436
Pennsylvania(2)	—	—	—	151

Total	20	10,479	1,298,864	$	229,450

(1) Includes annexes to existing properties.
(2) Land acquisitions with no incremental storage.

During the year ended December 31, 2023, we entered into an agreement to sell, to an unrelated third party, 71 wholly-owned self storage properties consisting of approximately 4.4 million rentable square feet configured in approximately 34,000 storage units for approximately $530.0 million. The agreement provided for separate disposition dates with 32 self storage properties, consisting of approximately 2.0 million rentable square feet configured in approximately 16,000 storage units for approximately $263.2 million, sold during 2023, and 39 self storage properties, consisting of approximately 2.4 million rentable square feet configured in approximately 18,000 storage units for approximately $266.8 million, to be sold during 2024.

During the year ended December 31, 2023, we entered into an agreement to contribute to the 2024 Joint Venture, 56 wholly-owned self storage properties consisting of approximately 3.2 million rentable square feet configured in approximately 24,000 storage units for approximately $346.5 million. These 56 properties were contributed to the 2024 Joint Venture during 2024.

During the year ended December 31, 2022, we acquired 45 consolidated self storage properties, of which five were acquired by us from our PROs and 40 were acquired by us from third-party sellers. The following is a summary of our 2022 consolidated acquisition activity (dollars in thousands):


	Number of	Number of	Rentable
State	Properties	Units	Square Feet	Fair Value
2022 Acquisitions:
Georgia	11	5,737	813,287	$	158,134
Florida	7	3,604	460,574	104,350
Pennsylvania	5	2,818	374,654	65,078
Texas	4	2,491	320,287	29,790
South Carolina	4	2,391	314,063	71,338
New Mexico	4	1,559	229,454	20,162
Arkansas	2	1,206	196,925	16,897
Colorado	2	671	107,328	14,106
Other(1)	6	4,492	396,477	89,321
Total	45	24,969	3,213,049	$	569,176

(1) Self storage properties in other states acquired during the year ended December 31, 2022 include Alabama, Connecticut, Minnesota, Missouri, New York and Virginia.

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Our Unconsolidated Real Estate Ventures

We seek to opportunistically partner with institutional funds and other institutional investors to acquire attractive portfolios utilizing a promoted return structure. We believe there is significant opportunity for continued external growth by partnering with institutional investors seeking to deploy capital in the self storage industry.

2024 Joint Venture

Subsequent to December 31, 2023, we entered into the 2024 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest. During 2024, we contributed 56 self storage properties containing approximately 3.2 million rentable square feet, configured in over 24,000 storage units and located across seven states.

2023 Joint Venture

As of December 31, 2023, our 2023 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest, did not own or operate any self storage properties. The 2023 JV Agreement allows for equity capital contributions of up to $400 million from the 2023 JV Members over a 24 month period starting in December 2023, with options to extend the investment time period by two additional six month periods.

2018 Joint Venture

As of December 31, 2023, our 2018 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest, owned and operated 104 self storage properties containing approximately 7.8 million rentable square feet, configured in over 64,000 storage units and located across 17 states.

2016 Joint Venture

As of December 31, 2023, our 2016 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest, owned and operated a portfolio of 81 properties containing approximately 5.7 million rentable square feet, configured in approximately 47,000 storage units and located across 13 states.

Our Competitive Strengths

We believe our property management platform combined with our unique PRO structure allows us to differentiate ourselves from other self storage operators, and the following competitive strengths enable us to effectively compete against our industry peers:

High Quality Properties in Key Growth Markets. We held ownership interests in and operated a geographically diversified portfolio of 1,050 self storage properties located in 42 states and Puerto Rico, comprising approximately 68.6 million rentable square feet, configured in approximately 542,000 storage units as of December 31, 2023, excluding 39 self storage properties classified as held for sale to be sold to a third party in 2024. Over 70% of our consolidated portfolio is located in the top 100 MSAs, based on our 2023 net operating income ("NOI"). We believe that these properties are primarily located in high quality growth markets that have attractive supply and demand characteristics and are less sensitive to the fluctuations of the general economy. Many of these markets have multiple barriers to entry against increased supply, including zoning restrictions against new construction and new construction costs that we believe are higher than our properties' fair market value. Furthermore, we believe that our significant size and the overall geographic diversification of our portfolio reduces risks associated with specific local or regional economic downturns or natural disasters.

Integrated Platform Utilizing Advanced Technology for Enhanced Operational Performance and Best Practices. Our national platform allows us to capture cost savings through integration and centralization, thereby eliminating redundancies and utilizing economies of scale across the property management platforms of us and our PROs. As compared to a stand-alone operator, our national platform has greater access to lower-cost capital, reduced Internet marketing costs per customer lead, discounted property insurance expense, and reduced overhead costs. In addition, the Company has sufficient scale for various centralized functions, including financial reporting, the operation of call centers, expanding cell tower leasing, a national credit card processing program, marketing, information technology, legal support, and capital market functions, to achieve substantial cost savings over smaller, individual operators.

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Our national platform utilizes advanced technology for our data warehouse program, Internet marketing, our centralized call centers, financial and property analytic dashboards, revenue optimization analytics and expense management tools to enhance operational performance. These centralized programs, which are run through our Technology and Best Practices Group, are positively impacting our business performance, and we believe that they will continue to be a driver of organic growth going forward. We will continue to utilize our Technology and Best Practices Group to help us benefit from the collective sharing of key operating strategies among our PROs in areas like human resource management, local marketing and operating procedures and building tenant insurance-related arrangements.

Differentiated, Growth-Oriented Strategy Focused on Established Operators. We are a self storage REIT with a unique PRO structure that supports our differentiated external growth strategy. Our PRO structure appeals to operators who are looking for access to growth capital while maintaining an economic stake in the self storage properties that each manages on our behalf. These attributes entice operators to join the Company rather than sell their properties for cash consideration. Through our PRO structure, we seek to attract operators who are confident in the future performance of their properties and desire to participate in the growth of the Company. We have successfully recruited established operators across the United States with a history of efficient property management and a track record of successful acquisitions. Our structure and differentiated strategy have enabled us to build a substantial captive pipeline of potential acquisition opportunities (our "captive pipeline") from existing operators as well as potentially create external growth from the recruitment of additional PROs.

Aligned Incentive Structure with Shareholder Downside Protection. Our PRO structure promotes operator accountability as subordinated performance units issued to our PROs in exchange for the contribution of their properties are entitled to distributions only after those properties satisfy minimum performance thresholds. In the event of a material reduction in operating cash flow, distributions on our subordinated performance units will be reduced before or disproportionately to distributions on our common shares held by our common shareholders. In addition, we expect our PROs will generally co-invest subordinated equity in the form of subordinated performance units in each acquisition that they source from a third-party seller, and the value of these subordinated performance units will fluctuate with the performance of their managed portfolios. Therefore, our PROs are incentivized to select acquisitions that are expected to exceed minimum performance thresholds, thereby increasing the value of their subordinated equity stake. We expect that our shareholders will benefit from the higher levels of property performance that our PROs are incentivized to deliver.

Our Business and Growth Strategies

By capitalizing on our competitive strengths, we seek to increase scale, achieve optimal revenue-producing occupancy and rent levels, and increase long-term shareholder value by achieving sustainable long-term growth. Our business and growth strategies to achieve these objectives are as follows:

Maximize Property Level Cash Flow. We strive to maximize the cash flows at our properties by leveraging the economies of scale provided by our national platform, including through the implementation of new ideas derived from our Technology and Best Practices Group. We believe that our efficient national platform, centralized infrastructure and unique PRO structure, will enable us to achieve optimal market rents and occupancy, reduce operating expenses and increase the sale by us and our PROs of ancillary products and services, including tenant insurance, of which we receive a portion of the proceeds, truck rentals and packing supplies.

Acquire Built-in Captive Pipeline of Target Properties from Existing PROs. We have an attractive, high quality potential acquisition pipeline of over 110 self storage properties valued at approximately $1.7 billion that will continue to drive our future growth. We consider a property to be in our captive pipeline if it (i) is under a management service agreement with one of our PROs, (ii) meets our property quality criteria, and (iii) is either required to be offered to us under the applicable facilities portfolio management agreement or a PRO has a reasonable basis to believe that the controlling owner of the property intends to sell the property in the next seven years.

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Our PROs have management service agreements with all of the properties in our captive pipeline and hold controlling and non-controlling ownership interests in some of these properties. With respect to each property in our captive pipeline in which a PRO holds a controlling ownership interest, such PRO has agreed that it will not transfer (or permit the transfer of, to the extent possible) any interest in such self storage property without first offering or causing to be offered (if permissible) such interest to us. In addition, upon maturity of the outstanding mortgage indebtedness encumbering such property, so long as occupancy is consistent with or exceeds average local market levels, which we determine in our sole discretion, such PRO has agreed to offer or cause to be offered (if permissible) such interest to us. With respect to captive pipeline properties in which our PROs have a non-controlling ownership interest or no ownership interest, each PRO has agreed to use commercially reasonable good faith efforts to facilitate our purchase of such property. We preserve the discretion to accept or reject any of the properties that our PROs are required to, or elect to, offer (or cause to be offered) to us.

Access Additional Off-Market Acquisition Opportunities. Our PROs have established an extensive network of industry relationships and contacts in their respective markets. Through these local connections, our PROs are able to access acquisition opportunities that are not publicly marketed or sold through auctions. Our structure incentivizes our PROs to source acquisitions in their markets from third-party sellers and consolidate these properties into the Company. We believe our PROs' networks, their industry expertise and close familiarity with the other operators in their markets provide us with a clear competitive advantage in identifying and selecting attractive acquisition opportunities, in many cases, before they are publicly marketed. Additionally, we have established a corporate acquisitions team that, through relationships with our PROs and other market participants, sources acquisition opportunities whereby the properties will be managed by our corporate property management team. We believe our reputation as a reliable, well-capitalized buyer, along with our use of OP units as transactional currency which offers a tax-deferred transaction to self storage owners seeking to sell their properties, gives us a competitive advantage over self storage companies that do not have the same transactional history or currency as us.

Recruit Additional New PROs in Target Markets. We intend to continue to execute on our external growth strategy through additional acquisitions and contributions from future PROs in key markets. We believe there is significant opportunity for growth through consolidation of the highly fragmented composition of the market. We believe that future operators will be attracted to our unique PRO structure, providing them with lower cost of capital, better economies of scale, and greater operational and overhead efficiencies while preserving their existing property management platforms. We intend to add one to three additional PROs to complement our existing geographic footprint and to achieve our goal of creating a highly diversified nationwide portfolio of properties focused in the top 100 MSAs. When considering a PRO candidate, we consider various factors, including the size of the potential PRO's portfolio, the quality and location of its properties, its market exposure, its operating expertise, its ability to grow its business, and its reputation with industry participants.

Strategic Joint Venture Arrangements. We intend to continue to opportunistically partner with institutional funds and other institutional investors to acquire attractive portfolios utilizing a promoted return structure. We believe there is significant opportunity for continued external growth by partnering with institutional investors seeking to deploy capital in the self storage industry. We intend to leverage our property management platform to provide property and asset management services for future strategic joint ventures, generating additional operating profits and third party fee income. In addition, we consider the 75% third-party interest in our unconsolidated real estate ventures, which as of December 31, 2023 owned 185 properties, to present a potential acquisition opportunity. This 75% third-party share of gross real estate assets is approximately $1.7 billion based on the historical book value of the joint ventures. Were we to pursue an acquisition of these interests, it could potentially drive our future growth. We have entered into agreements for two additional joint ventures and during 2024, we have contributed an additional 56 properties to the 2024 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8).

Our Financing Strategy

We expect to maintain a flexible approach in financing new property acquisitions. In general, we expect to fund our property acquisitions through a combination of borrowings under bank credit facilities (including term loans and revolving facilities), property-level debt, issuances of OP equity and public and private equity and debt issuances.

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As of December 31, 2023, our unsecured credit facility provided for total borrowings of $1.955 billion (the "credit facility"). The credit facility consists of the following components: (i) a revolving line of credit (the "Revolver") which provided for a total borrowing commitment up to $950.0 million, under which we could borrow, repay and re-borrow amounts, (ii) a $275.0 million tranche B term loan facility (the "Term Loan B"), (iii) a $325.0 million tranche C term loan facility (the "Term Loan C"), (iv) a $275.0 million tranche D term loan facility (the "Term Loan D") and (v) a $130.0 million tranche E term loan facility (the "Term Loan E"). As of December 31, 2023, we had the entire amounts drawn on Term Loan B, Term Loan C, Term Loan D and Term Loan E and we had $381.0 million of outstanding borrowings under the Revolver, and the capacity to borrow an additional $562.6 million under the Revolver while remaining in compliance with the credit facility's financial covenants. As of December 31, 2023, we had an expansion option under the credit facility, which, if exercised in full, would have provided for a total credit facility of $2.5 billion.

We have a credit agreement with a lender for a term loan facility that matures in December 2028 (the "2028 Term Loan Facility") and is separate from the credit facility in an aggregate amount of $75.0 million. As of December 31, 2023 the entire amount was outstanding under the 2028 Term Loan Facility with an effective interest rate of 4.62%. We have an expansion option under the 2028 Term Loan Facility, which, if exercised in full, would provide for total borrowings in an aggregate amount up to $125.0 million.

We have a credit agreement with a lender for a term loan facility that matures in April 2029 (the "April 2029 Term Loan Facility") and is separate from the credit facility and 2028 Term Loan Facility in an aggregate amount of $100.0 million. As of December 31, 2023 the entire amount was outstanding under the April 2029 Term Loan Facility with an effective interest rate of 4.27%.

We have a June 2029 Term Loan Facility that matures in June 2029 (the "June 2029 Term Loan Facility") and is separate from the credit facility, 2028 Term Loan Facility, and April 2029 Term Loan Facility in an aggregate amount of $285.0 million. As of December 31, 2023, the June 2029 Term Loan Facility had an effective interest rate of 5.37%. We have an expansion option under the June 2029 Term Loan Facility, which, if exercised in full, would provide for total borrowings in an aggregate amount up to $300.0 million.

The credit facility, 2028 Term Loan Facility, April 2029 Term Loan Facility and the June 2029 Term Loan Facility each contain the same financial covenants and customary affirmative and negative covenants that, among other things, could limit the Company's ability to make distributions or certain investments, incur debt, incur liens and enter into certain transactions.

On August 30, 2019, our operating partnership issued $100.0 million of 3.98% senior unsecured notes due August 30, 2029 (the "2029 Notes") and $50.0 million of 4.08% senior unsecured notes due August 30, 2031 (the "August 2031 Notes") in a private placement to certain institutional investors.

On October 22, 2020, our operating partnership issued $150.0 million of 2.99% senior unsecured notes due August 5, 2030 (the "August 2030 Notes") and $100.0 million of 3.09% senior unsecured notes due August 5, 2032 (the "August 2032 Notes").

On May 26, 2021, our operating partnership issued $55.0 million of 3.10% senior unsecured notes due May 4, 2033 (the "May 2033 Notes").

On July 26, 2021, our operating partnership issued $35.0 million of 2.16% senior unsecured notes due May 4, 2026 (the "May 2026 Notes") and $90.0 million of 3.00% senior unsecured notes due May 4, 2031 (the "May 2031 Notes").

On December 14, 2021, our operating partnership issued $75.0 million of 2.72% senior unsecured notes due November 30, 2030 (the "November 2030 Notes"), $175.0 million of 2.81% senior unsecured notes due November 30, 2031 (the "November 2031 Notes") and $75.0 million of 3.06% senior unsecured notes due November 30, 2036 (the "2036 Notes").

On January 28, 2022, our operating partnership issued $125.0 million of 2.96% senior unsecured notes due November 30, 2033 (the "November 2033 Notes").

On September 28, 2022, our operating partnership issued $200.0 million of 5.06% senior unsecured notes due November 16, 2032 (the "November 2032 Notes").

On April 27, 2023, our operating partnership issued $120.0 million of 5.61% senior unsecured notes due July 5, 2028 (the "July 2028 Notes"). As of December 31, 2023, the July 2028 Notes had an effective interest rate of 5.75%.

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On October 5, 2023, our operating partnership issued $65.0 million of 6.46% senior unsecured notes due October 5, 2026 (the "October 2026 Notes"), $100.0 million of 6.55% senior unsecured notes due October 5, 2028 (the "October 2028 Notes"), $35.0 million of 6.66% senior unsecured notes due October 5, 2030 (the "October 2030 Notes") and $50.0 million of 6.73% senior unsecured notes due October 5, 2033 (the "October 2033 Notes" and together with the May 2026 Notes, October 2026 Notes, July 2028 Notes, October 2028 Notes, 2029 Notes, August 2030 Notes, October 2030 Notes, November 2030 Notes, May 2031 Notes, August 2031 Notes, November 2031 Notes, August 2032 Notes, November 2032 Notes, May 2033 Notes, November 2033 Notes and 2036 Notes, the "Senior Unsecured Notes") in a private placement to certain institutional investors.

The Senior Unsecured Notes are subject to customary affirmative and negative covenants that, among other things, limit the Company's ability to make distributions or certain investments, incur debt, incur liens and enter into certain transactions.

We expect to employ leverage in our capital structure in amounts determined from time to time by our board of trustees. Although our board of trustees has not adopted a policy which limits the total amount of indebtedness that we may incur, it will consider a number of factors in evaluating our level of indebtedness from time to time, as well as the amount of such indebtedness that will be either fixed and variable-rate, and in making financial decisions, including, among others, the following:

•the interest rate of the proposed financing;

•the extent to which the financing impacts our flexibility in managing our properties;

•prepayment penalties and restrictions on refinancing;

•the purchase price of properties we acquire with debt financing;

•our long-term objectives with respect to the financing;

•our target investment returns;

•the ability of particular properties, and the Company as a whole, to generate cash flow sufficient to cover expected debt service payments;

•overall level of consolidated indebtedness;

•timing of debt maturities;

•provisions that require recourse and cross-collateralization;

•corporate credit ratios including debt service coverage, debt to total market capitalization and debt to undepreciated assets; and

•the overall ratio of fixed- and variable-rate debt.

Our indebtedness may be recourse, non-recourse or cross-collateralized. If the indebtedness is non-recourse, the collateral will be limited to the particular properties to which the indebtedness relates. In addition, we may invest in properties subject to existing loans secured by mortgages or similar liens on our properties, or may refinance properties acquired on a leveraged basis. We may use the proceeds from any borrowings to refinance existing indebtedness, to refinance investments, including the redevelopment of existing properties, for general working capital or for other purposes when we believe it is advisable.

Dividend Reinvestment Plan

In the future, we may adopt a dividend reinvestment plan that will permit shareholders who elect to participate in the plan to have their cash dividends reinvested in additional common shares.

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Regulation

General

Generally, self storage properties are subject to various laws, ordinances and regulations, including those relating to lien sale rights and procedures, public accommodations, insurance, and the environment. Changes in any of these laws, ordinances or regulations could increase the potential liability existing or created by tenants or others on our properties. Laws, ordinances, or regulations affecting development, construction, operation, upkeep, safety and taxation requirements may result in significant unanticipated expenditures, loss of self storage sites or other impairments to operations, which would adversely affect our cash flows from operating activities.

Under the Americans with Disabilities Act of 1990 (the "ADA"), all places of public accommodation are required to meet certain federal requirements related to access and use by disabled persons. A number of additional U.S. federal, state and local laws may also require modifications to our properties, or restrict certain further renovations of the properties, with respect to access thereto by disabled persons. The ADA or these other laws may also apply to our websites. For additional information on the ADA, see "Item 1A. Risk Factors—Risks Related to Our Business—Costs associated with complying with the ADA may result in unanticipated expenses."

Insurance activities are subject to state insurance laws and regulations as determined by the particular insurance commissioner for each state in accordance with the McCarran-Ferguson Act, as well as subject to the Gramm-Leach-Bliley Act and the privacy regulations promulgated by the Federal Trade Commission pursuant thereto.

Under various U.S. federal, state and local laws, ordinances and regulations, owners and operators of real estate may be liable for the costs of investigating and remediating certain hazardous substances or other regulated materials on or in such property. The Comprehensive Environmental Response Compensation and Liability Act of 1980, as amended ("CERCLA") and comparable state laws typically impose strict joint and several liabilities without regard to whether the owner or operator knew of, or was responsible for, the presence of such substances or materials. The presence of such substances or materials, or the failure to properly remediate such substances, may adversely affect the owner's or operator's ability to lease, sell or rent such property or to borrow using such property as collateral. Persons who arrange for the disposal or treatment of hazardous substances or other regulated materials may be liable for the costs of removal or remediation of such substances at a disposal or treatment facility, whether or not such facility is owned or operated by such person. Certain environmental laws impose liability for release of asbestos-containing materials into the air and third-parties may seek recovery from owners or operators of real properties for personal injury associated with asbestos-containing materials. Certain environmental laws also impose liability, without regard to knowledge or fault, for removal or remediation of hazardous substances or other regulated materials upon owners and operators of contaminated property. Moreover, the past or present owner or operator of a property from which a release emanates could be liable for any personal injuries or property damages that may result from such releases, as well as any damages to natural resources that may arise from such releases. Certain environmental laws impose compliance obligations on owners and operators of real property with respect to the management of hazardous materials and other regulated substances. For example, environmental laws govern the management of asbestos-containing materials and lead-based paint. Failure to comply with these laws can result in penalties or other sanctions. In connection with the ownership, operation and management of our current or past properties and any properties that we may acquire and/or manage in the future, we could be legally responsible for environmental liabilities or costs relating to a release of hazardous substances or other regulated materials at or emanating from such property. In order to assess the potential for such liability, we conduct an environmental assessment of each property prior to acquisition and manage our properties in accordance with environmental laws while we own or operate them. We have engaged qualified, reputable and adequately insured environmental consulting firms to perform environmental site assessments of all of our properties prior to acquisition and are not aware of any environmental issues that are expected to materially impact the operations of any property. For additional information on environmental matters and regulation, see "Item 1A. Risk Factors—Risks Related to Our Business—Environmental compliance costs and liabilities associated with operating our properties may affect our results of operations."

Property management activities are often subject to state real estate brokerage laws and regulations as determined by the particular real estate commission for each state. We may be required to comply with various state privacy statutes in connection with the operation of our business. In addition, we may be required to comply with federal, state and local laws, rules and regulations in connection with our communications with our tenants or prospective tenants, including with respect to available units, reservations, payments due, and other matters.

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REIT Qualification

We have elected and we believe that we have qualified to be taxed as a REIT under the Internal Revenue Code of 1986, as amended, (the "Code"), commencing with our taxable year ended on December 31, 2015. We generally will not be subject to U.S. federal income tax on our net taxable income to the extent that we distribute annually all of our net taxable income to our shareholders and maintain our qualification as a REIT. We believe that we have been organized and have operated in conformity with the requirements for qualification and taxation as a REIT under the Code, and we expect that our intended manner of operation will enable us to continue to meet the requirements for qualification and taxation as a REIT. To qualify, and maintain our qualification, as a REIT, we must meet on a continuing basis, through our organization and actual investment and operating results, various requirements under the Code relating to, among other things, the sources of our gross income, the composition and values of our assets, our distribution levels and the diversity of ownership of our shares. If we fail to qualify as a REIT in any taxable year and do not qualify for certain statutory relief provisions, we will be subject to U.S. federal income tax at regular corporate rates and may be precluded from qualifying as a REIT for the subsequent four taxable years following the year during which we failed to qualify as a REIT. Even if we qualify for taxation as a REIT, we still may be subject to some U.S. federal, state and local taxes on our income or assets. In addition, subject to maintaining our qualification as a REIT, a portion of our business is conducted through, and a portion of our income is earned by, one or more taxable REIT subsidiaries ("TRSs"), which are subject to U.S. federal corporate income tax at regular rates. Distributions paid by us generally will not be eligible for taxation at the preferential U.S. federal income tax rates that currently apply to certain distributions received by individuals from taxable corporations, unless such distributions are attributable to dividends received by us from a TRS.

Competition

We compete with many other entities engaged in real estate investment activities for customers and acquisitions of self storage properties and other assets, including national, regional, and local owners, operators, and developers of self storage properties. We compete based on a number of factors including location, rental rates, security, suitability of the property's design to prospective tenants' needs, and the manner in which the property is operated and marketed. We believe that the primary competition for potential customers comes from other self storage properties within a three to five mile radius. We have positioned our properties within their respective markets as high-quality operations that emphasize tenant convenience, security, and professionalism.

We also may compete with numerous other potential buyers when pursuing a possible property for acquisition, which can increase the potential cost of a project. These competing bidders also may possess greater resources, or have a lower cost of capital, than us and therefore be in a better position to acquire a property. However, our use of OP units and subordinated performance units as transactional currency allows us to structure our acquisitions in tax-deferred transactions. As a result, potential targets who are tax-sensitive might favor us as a suitor.

Our primary national competitors in many of our markets for both tenants and acquisition opportunities include local and regional operators, institutional investors, private equity funds, as well as the other public self storage REITs, including Public Storage, CubeSmart, and Extra Space Storage Inc. These entities also seek financing through similar channels to the Company. Therefore, we will continue to compete for institutional investors in a market where funds for real estate investment may decrease.

Human Capital

We seek to foster a diverse and inclusive work environment that values each individual team member’s talents and contributions, while channeling those efforts toward our common core values of integrity, accountability, humility and compassion. Our success relies on the general professionalism of our employees and our PRO's site managers and staff which are contributing factors to a site's ability to successfully secure rentals, retain tenants and maintain clean and secure self storage properties. We seek to increase employee retention and well-being and our team members enjoy a robust benefit package that includes medical, dental, vision, life insurance, 401K with matching employer contribution and a performance-based bonus incentive plan. We also seek to promote diversity among our employees and management team. As of December 31, 2023, approximately 63% of our employees were women and 32% of our senior management team (Director level and above) were women, including Tamara Fischer, our Executive Chairperson of our Board of Trustees.

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As of December 31, 2023, we had 1,108 employees, which includes employees of our property management platform but does not include persons employed by our PROs. As of December 31, 2023, our PROs, collectively, had approximately 600 full-time and part-time employees involved in management, operations, and reporting with respect to our self storage property portfolio.

Available Information

We file registration statements, proxy statements, our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and all amendments to those statements and reports with the Securities and Exchange Commission (the "SEC"). Investors may obtain copies of these statements and reports by accessing the SEC's website at www.sec.gov. Our statements and reports and any amendments to any of those statements and reports that we file with the Securities and Exchange Commission are available free of charge as soon as reasonably practicable on our website at www.nationalstorageaffiliates.com. The information contained on our website is not incorporated into this Annual Report on Form 10-K. Our common shares are listed on the New York Stock Exchange under the symbol "NSA."

Item 1A. Risk Factors

An investment in our common shares involves a high degree of risk. Before making an investment decision, you should carefully consider the following risk factors, together with the other information contained in this Annual Report on Form 10-K. If any of the risks discussed in this Annual Report on Form 10-K occurs, our business, financial condition, liquidity and results of operations could be materially and adversely affected.

Risks Related to our Business

Adverse economic or other conditions in the markets in which we do business and more broadly associated with the real estate industry could negatively affect our occupancy levels and rental rates and therefore our operating results and the value of our self storage properties.

Our operating results are dependent upon our ability to achieve optimal occupancy levels and rental rates at our self storage properties. Adverse economic or other conditions in the markets in which we do business, particularly in our markets in Texas, California, Florida, Georgia, and Oregon, which accounted for approximately 17%, 12%, 11%, 6%, and 6%, respectively, of our total rental and other property-related revenues for the year ended December 31, 2023, may lower our occupancy levels and limit our ability to maintain or increase rents or require us to offer rental discounts. No single customer represented a significant concentration of our 2023 revenues. However, our property portfolio consists solely of self storage properties and is therefore subject to risks inherent in investments in a single industry. The following adverse developments, among others, in the markets in which we do business may adversely affect the operating performance of our properties or our financial results:

•business layoffs or downsizing, industry slowdowns, relocation of businesses and changing demographics;

•periods of economic slowdown, recession, high interest rates, or inflationary environments, declining demand for self storage generally or in a particular area or the public perception that any of these events may occur;

•local or regional real estate market conditions, such as competing properties or products, the oversupply of self storage, or vacancies or changes in self storage space market rents;

•perceptions by prospective tenants of the safety, convenience and attractiveness of our properties and the neighborhoods in which they are located; and

•other events affecting or shifting consumer discretionary spending.

Any of the above events may reduce our rental revenues, impair our operating results, and reduce our ability to satisfy our debt service obligations and make cash distributions to our shareholders, and the effect of the foregoing may be greater than it would be were our investments not limited to a single industry.

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We may not be successful in identifying and consummating suitable acquisitions, adding additional suitable new PROs, or integrating and operating such acquisitions, including integrating them into our financial and operational reporting infrastructure and internal control framework in a timely manner, which may impede our growth.

Our ability to expand through acquisitions is integral to our business strategy and requires us to identify suitable acquisition candidates or investment opportunities that meet our criteria and are compatible with our growth strategy. We may not be successful in identifying suitable properties or other assets that meet our acquisition criteria or in consummating acquisitions on satisfactory terms or at all. Failure to identify or consummate acquisitions will slow our growth, which could in turn adversely affect our share price.

For the potential acquisitions in our captive pipeline, we have not entered into negotiations with the respective owners of these properties and there can be no assurance as to whether we will acquire any of these properties or the actual timing of any such acquisitions. Each captive pipeline property is subject to additional due diligence and the determination by us to pursue the acquisition of the property. In addition, with respect to the captive pipeline properties in which our PROs have a non-controlling ownership interest or no ownership interest, the current owner of each property is not required to offer such property to us and there can be no assurance that we will acquire these properties.

Our ability to acquire properties on favorable terms and successfully integrate and operate them, including integrating them into our financial and operational reporting infrastructure in a timely manner, may be constrained by the following significant risks:

•we face competition from national, regional and local owners, operators and developers of self storage properties, which may result in higher property acquisition prices and reduced yields;

•we may not be able to achieve satisfactory completion of due diligence investigations and other customary closing conditions;

•we may fail to finance an acquisition on favorable terms or at all;

•we may spend more time and incur more costs than budgeted to make necessary improvements or renovations to, and to integrate and operate, acquired properties; and

•we may acquire properties subject to liabilities without any recourse, or with only limited recourse, with respect to unknown liabilities such as liabilities for clean-up of undisclosed environmental contamination, tax liabilities, claims by persons dealing with the former owners of the properties and claims for indemnification by general partners, trustees, officers and others indemnified by the former owners of the properties.

The contributors of properties may make limited representations and warranties to us about the properties and may agree to indemnify us up to a specified amount for a certain period of time following the closing for breaches of those representations and warranties. However, any resulting liabilities identified may not fall within the scope or time frame covered by the indemnification, and we may be required to bear those liabilities, which may materially and adversely affect our operating results, financial condition and business.

We face competition for tenants.

We compete with many other entities engaged in real estate investment activities for tenants, including national, regional and local owners, operators and developers of self storage properties. Actions by our competitors may decrease or prevent increases in the occupancy and rental rates, while increasing the operating expenses, of our properties.

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Increases in taxes and regulatory compliance costs, including as a result of changes in law or property reassessments, may reduce our income and adversely impact our cash flows.

Increases in income or other taxes generally are not passed through to tenants under leases and may reduce or negatively impact our net income, funds from operations ("FFO"), core FFO, cash flows, financial condition, ability to pay or refinance our debt obligations, ability to make cash distributions to shareholders, and the trading price of our securities. In addition, the value of our properties may be reassessed for property tax purposes by taxing authorities including as a result of our acquisition activities. For example, our property taxes could increase due to changes in tax rates or removal of limitations on the amount by which our property taxes or property reassessments may increase. From time to time, proposals have been made to remove certain limits on annual real estate tax increases of assessed value of real property in California, where we currently have 87 consolidated properties and 12 unconsolidated properties. While no such initiative has yet been successful, to the extent a similar future initiative is successful, our property tax expense could increase substantially, which could adversely impact our operating results, cash flow, and our ability to pay any expected dividends to our shareholders.

Similarly, in response to facing severe budgetary problems, many states and jurisdictions are considering or implementing changes in laws such as increasing sales taxes, increasing the potential liability for environmental conditions existing on properties, increasing the restrictions on discharges or other conditions, or mandating paid family leave for employees, which may result in significant unanticipated expenditures, which could result in similar adverse effects.

Our storage leases are relatively short-term in nature, which exposes us to the risk that we may have to re-lease our units and we may be unable to do so on attractive terms, on a timely basis or at all.

Our storage leases are relatively short-term in nature, typically month-to-month, which exposes us to the risk that we may have to re-lease our units frequently and we may be unable to do so on attractive terms, on a timely basis or at all. Because these leases generally permit the tenant to leave at the end of the month without penalty, our revenues and operating results may be impacted by declines in market rental rates more quickly than if our leases were for longer terms. In addition, any delay in re-leasing units as vacancies arise would reduce our revenues and harm our operating results.

Security breaches through cyber-attacks, cyber-intrusions, or other methods could disrupt our information technology networks and related systems.

We and our PROs are increasingly dependent upon automated information technology processes and Internet commerce, and many of our and their tenants come from the telephone or over the Internet. Moreover, the nature of our and our PROs' business involves the receipt and retention of certain personal information about such tenants. In many cases, we and our PROs also rely significantly on third-party vendors to retain data, process transactions and provide other systems services. Our networks and operations could be disrupted, and sensitive data could be compromised, by physical or electronic security breaches, targeted against us, our PROs, our vendors or other organizations, including financial markets or institutions, including by way of or through cyber-attacks or cyber-intrusions over the Internet, malware, computer viruses, attachments to e-mails, phishing, employee theft or misuse, or inadequate security controls. Although we make efforts to protect the security and integrity of our networks and systems, there can be no assurance that these efforts and measures will be effective or that attempted security breaches or disruptions would not be successful, as such attacks and breaches may be difficult to detect (or not detected at all) and are becoming more sophisticated. In such event, we may experience business interruptions; data loss, ransom, misappropriation, or corruption; theft or misuse of confidential or proprietary information; or litigation and investigation by tenants, governmental or regulatory agencies, or other third parties, which could result in the payment of fines, penalties and other damages. Such events could also have other adverse impacts on us, including breaches of debt covenants, other contractual or REIT compliance obligations, or late or misstated financial reports, and significant diversion of management attention and resources. As a result, such events could have a material adverse effect on our financial condition, results of operations and cash flows and harm our business reputation or have such effects on our PROs.

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Costs associated with complying with the ADA may result in unanticipated expenses.

Under the ADA and other federal, state and local laws, we are required to meet certain requirements related to access and use by disabled persons. Noncompliance with the ADA could result in the imposition of fines or an award of damages to private litigants and also could result in an order to correct any non-complying feature, which could result in substantial capital expenditures. If one or more of our properties or websites is not in compliance with the ADA or similar laws, then we would be required to incur additional costs to bring the property or websites into compliance. If we incur such costs and they are substantial, our financial condition, results of operations, cash flow, per share trading price of our common shares and our ability to satisfy our debt service obligations and to make cash distributions to our shareholders could be adversely affected.

Environmental compliance costs and liabilities associated with operating our properties may affect our results of operations.

Under various U.S. federal, state and local environmental laws, ordinances and regulations, owners and operators of real estate may be liable for the costs of investigating and remediating certain hazardous substances or other regulated materials on or in such property. No assurances can be given that existing environmental studies with respect to any of our properties reveal all environmental liabilities, that any prior owner or operator of our properties did not create any material environmental condition not known to us, or that a material environmental condition does not otherwise exist as to any one or more of our properties. There also exists the risk that material environmental conditions, liabilities or compliance concerns may have arisen after the review was completed or may arise in the future. Finally, future laws, ordinances or regulations and future interpretations of existing laws, ordinances or regulations may impose additional material environmental liability.

We and certain of our PROs have tenant insurance- and/or tenant protection plan-related arrangements that are in some cases subject to state-specific governmental regulation, which may adversely affect our results.

We and certain of our PROs have tenant insurance- and/or tenant protection plan-related arrangements with regulated insurance companies and our tenants. Some of our PROs earn access fees in connection with these arrangements. We receive a portion of the fees from these PROs. The tenant insurance and tenant protection plan businesses, including the payments associated with these arrangements, are in some cases subject to state-specific governmental regulation. State regulatory authorities generally have broad discretion to grant, renew and revoke licenses and approvals, to promulgate, interpret and implement regulations, and to evaluate compliance with regulations through periodic examinations, audits and investigations of the affairs of insurance industry participants. As a result of such action, we may be temporarily or permanently suspended from continuing some or all of our tenant insurance- and/or tenant protection plan-related activities, or otherwise fined or penalized or suffer an adverse judgment, which could adversely affect our business and results of operations.

Privacy concerns could result in regulatory changes that may harm our business.

Personal privacy has become a significant issue in the jurisdictions in which we operate. Many jurisdictions in which we operate have imposed or in the future may impose restrictions and requirements on the use of personal information by those collecting such information. For example, the California Consumer Privacy Act of 2018, which became effective as of January 1, 2020, together with the California Privacy Rights Act, provides consumers with expansive rights and control over personal information obtained by or shared with certain covered businesses. Changes to law or regulations or the passage of new laws affecting privacy, if applicable to our business, could impose additional costs and liability on us and could limit our use and disclosure of such information.

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We face possible risks and costs associated with the effects of climate change and severe weather.

We cannot predict the rate at which climate change will progress. However, the physical effects of climate change could have a material adverse effect on our properties, operations, and business. To the extent that climate change impacts changes in weather patterns, our markets could experience severe weather, including hurricanes, tornados, earthquakes, severe winter storms, wildfires and coastal flooding due to increases in storm intensity and rising sea levels. Over time, these conditions could result in declining demand for storage at our properties or in our inability to operate them at all. Climate change and severe weather may also have indirect effects on our business by increasing the cost of, or decreasing the availability of, property insurance, utilities or other important vendor services on terms we find acceptable, by increasing the costs of energy, maintenance, repair of fire, water and/or wind damage, and snow removal at our properties. There can be no assurance that climate change and severe weather, or the potential impacts of these events on our vendors, will not have a material adverse effect on our properties, operations, or business

Changes in federal, state, and local legislation and regulation as well as international pacts or treaties based on concerns about climate change could result in increased capital expenditures on our existing properties (for example, to improve their energy efficiency and/or resistance to severe weather) without a corresponding increase in revenue, which may result in adverse impacts to our net income. In recent years, there have been a number of new legal efforts to reduce greenhouse gas emissions and to take other similar actions to combat the effects of climate change, including at the international level and at the U.S. federal, state and local levels.

Uninsured losses or losses in excess of our insurance coverage could adversely affect our financial condition, operating results and cash flow.

We maintain comprehensive liability, fire, flood, earthquake, wind (as deemed necessary or as required by our lenders), extended coverage and rental loss insurance with respect to our properties. Certain types of losses, however, may be either uninsurable or not economically insurable either in total or in part (due to location or otherwise), such as losses due to earthquakes, hurricanes, tornadoes, floods, riots, acts of war or terrorism. Should an uninsured loss occur, we could lose both our investment in and anticipated profits and cash flow from a property or otherwise be subject to significant liabilities. In addition, if any such loss is insured, we may be required to pay significant amounts on any claim for recovery of such a loss prior to our insurer being obligated to reimburse us for the loss, or the amount of the loss may exceed our coverage for the loss. We currently self-insure a portion of our commercial insurance deductible risk through our captive insurance company. To the extent that our captive insurance company is unable to bear that risk, we may be required to fund additional capital to our captive insurance company or we may be required to bear that loss. As a result, our operating results may be adversely affected.

Illiquidity of real estate investments could significantly impede our ability to respond to adverse changes in the performance of our properties.

Because real estate investments are relatively illiquid and we have agreed and may in the future agree to certain transfer restrictions with respect to our properties, our ability to promptly sell one or more properties in our portfolio in response to changing economic, financial and investment conditions is limited. The real estate market is affected by many factors, such as general economic conditions, availability of financing, interest rates, supply and demand, and others, that are beyond our control. We cannot predict whether we will be able to sell any property for the price or on the terms set by us or whether any price or other terms offered by a prospective purchaser would be acceptable to us. We also cannot predict the length of time needed to find a willing purchaser and to close the sale of a property. In addition, we may be required to expend funds to correct defects or to make improvements before a property can be sold. We cannot assure you that we will have funds available to correct those defects or to make those improvements.

Our business could be harmed if key personnel terminate their employment with us.

Our success depends, to a significant extent, on the continued services of Arlen D. Nordhagen, Tamara D. Fischer, David G. Cramer, Brandon S. Togashi, William S. Cowan, Derek Bergeon and Tiffany S. Kenyon and the other members of our senior management team. We have entered into employment agreements with Mr. Nordhagen, Ms. Fischer, Mr. Cramer, Mr. Togashi, Mr. Cowan, Mr. Bergeon and Ms. Kenyon, which provide for an initial term of employment and automatic one-year extensions thereafter unless either party provides at least 90 days' notice of non-renewal. Notwithstanding these agreements, there can be no assurance that any of them will remain employed by us. The loss of services of one or more members of our senior management team could harm our business and our prospects. This risk may be heightened during periods of tight labor market conditions.

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We invest in strategic joint ventures that subject us to additional risks.

Some of our investments are, and in the future may be, structured as strategic joint ventures. Part of our strategy is to opportunistically partner with institutional funds and other institutional investors to acquire attractive portfolios through a promoted return structure. These arrangements are driven by the magnitude of capital required to complete the acquisitions and maintain the acquired portfolios. Such arrangements involve risks not present where a third party is not involved, including the possibility that partners or co-venturers might become bankrupt or otherwise fail to fund their share of required capital contributions. Additionally, partners or co-venturers might at any time have economic or other business interests or goals different from us and or in competition with us.

Joint ventures generally provide for a reduced level of control over an acquired project because governance rights are shared with others. Accordingly, certain major decisions relating to joint ventures, including decisions relating to, among other things, the approval of annual budgets, sales and acquisitions of properties, financings, and certain actions relating to bankruptcy, are often made by a majority vote of the investors or by separate agreements. In addition, such decisions may be subject to the risk that the partners or co-venturers may make certain decisions with which we do not agree or otherwise act in a manner that does not serve our best interests. Because we may not have the ability to exercise control over such operations, we may not be able to realize some or all of the benefits that we believe will be created from our involvement. At times, we and our partners or co-venturers may also each have the right to trigger a buy-sell arrangement, which could cause us to sell our interest, or acquire our partners' or co-venturers' interest, at a time when we otherwise would not have initiated such a transaction. If any of the foregoing were to occur, our business, financial condition and results of operations could suffer as a result.

Public health and other crisis, such as a highly infectious or contagious disease, could adversely impact or cause significant disruption to our financial condition, results of operations and cash flows.

We face various risks related to public health and other crises, such as the future outbreak of a highly infectious or contagious disease. The impact of such crises and the response of governments to combat the spread of these diseases, could, among other things, affect our tenants ability to meet their obligations to us, impact consumer discretionary spending, reduce new move-ins, compel complete or partial closures and operational changes at our properties, reduce demand for growth opportunities, such as acquiring new properties or adding new PROs, and interrupt the availability of our and our PROs' personnel. As a result, such crises could adversely impact our financial condition, results of operations and cash flows.

Terrorist attacks, active shooter incidents and other acts of violence or war may adversely impact our performance and may affect the markets on which our securities are traded.

Terrorist attacks at or against our stores, our interests, the United States or abroad, may negatively impact our operations and the value of our securities. Attacks, armed conflicts or active-shooter situations could negatively impact the demand for self-storage and increase of insurance coverage for our stores, which could reduce our profitability and cash flow. Furthermore, any terrorist attacks, armed conflicts or active-shooter situations could result in increased volatility in or damage to the United States and worldwide financial markets and economy.

Risks Related to Our Structure and Our Relationships with Our PROs

We may not be able to achieve the desired outcomes that the PRO structure is intended to produce.

As a means of incentivizing our PROs to drive operating performance and support the sustainability of the operating cash flow from the properties they manage on our behalf, we issued each PRO subordinated performance units aimed at aligning the interests of our PROs with our interests and those of our shareholders. The subordinated performance units are entitled to distributions exclusively tied to the performance of each PRO's managed portfolios but only after minimum performance thresholds are satisfied. Our issuance of such units, however, may have been and could be based on inaccurate valuations and thus misallocated, which would limit or eliminate the effectiveness of our intended incentive-based program.

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Our ability to terminate our facilities portfolio management agreements ("FPMAs") and asset management agreements ("AMAs") with a PRO is limited, which may adversely affect our ability to execute our business plan.

We may elect to terminate our FPMAs and AMAs with a PRO and transfer property management responsibilities over the properties managed by such PRO to us (or our designee), (i) upon certain defaults by a PRO as set forth in these agreements, or (ii) if the PRO's properties, on a portfolio basis, fail to meet certain predetermined performance thresholds for more than two consecutive calendar years or if the operating cash flow generated by the properties of the PRO for any calendar year falls below a level that will enable us to fund minimum levels of distributions, debt service payments attributable to the properties, and fund the properties' allocable operating expenses. Consequently, to the extent a PRO complies with these covenants, standards, and minimum requirements, we may not be able to terminate the applicable FPMAs and AMAs and transfer property management responsibilities over such properties to us (or our designee) even if our board believes that such PRO is not properly executing our business plan and/or is failing to operate its properties to their full potential. Moreover, transferring the management responsibilities over the properties managed by a PRO may be costly or difficult to implement or may be delayed, even if we are able to and believe that such a change in portfolio and property management would be beneficial to us and our shareholders.

We may less vigorously pursue enforcement of terms of agreements entered into with our PROs because of conflicts of interest with our PROs.

Our PROs are entities that have contributed self storage properties to us in exchange for ownership interests in us. As part of each transaction, our PROs make limited representations to us regarding the entities, properties and other assets to be acquired by us in the contribution and generally agree to indemnify us for 12 months after the closing of the contribution for breaches of such representations. Such indemnification is limited, however, and we are not entitled to any other indemnification in connection with the contributions. In addition, following each contribution from a PRO, the day-to-day operations of each of the managed properties will be managed by the PRO who was the principal of the applicable property portfolios prior to the contribution. In addition, certain key persons of our PROs are members of our board or our PRO advisory committee. Consequently, we may choose not to enforce, or to enforce less vigorously, our rights under these agreements and any other agreements with our PROs due to our desire to maintain our ongoing relationship with our PROs, which could adversely affect our operating results and business.

We own self storage properties in some of the same geographic regions as our PROs and may compete for tenants with other properties managed by our PROs.

Pursuant to our FPMAs, each PRO has agreed that, without our consent, the PRO will not, and it will cause its affiliates (other than Blue Sky's sub-manager) not to, enter into any new arrangements for the management of additional self storage properties within any PRO's assigned territory. However, we have not and will not acquire all of the self storage properties of our PROs. We will therefore own self storage properties in some of the same geographic regions as our PROs, and, as a result, we and our PROs may compete for tenants. This competition may affect our ability to attract and retain tenants and may reduce the rental rates we are able to charge, which could adversely affect our operating results and business.

Our PROs may engage in other activities, diverting their attention from the management of our properties, which could adversely affect the execution of our business plan and our operating results.

Our PROs and their employees and personnel are in the business of managing self storage properties. We have agreed that our PROs may continue to manage properties not included in our portfolio, and our PROs are not obligated to dedicate any specific employees or personnel exclusively to the management of our properties. As a result, their time and efforts may be diverted from the management of our properties, which could adversely affect the execution of our business plan and our operating results.

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When a PRO elects or is required to "retire" we may become exposed to new and additional costs and risks.

Under our FPMAs, after a two-year period following the initial contribution of their properties to us, a PRO may elect, or be required, to "retire" from the self storage business. Upon a retirement event, management of the properties will be transferred to us (or our designee) in exchange for OP units with a value equal to four times the average of the normalized annual EBITDA from the management contracts related to such PRO's managed portfolio over the immediately preceding 24-month period. As a result of this transfer, we may become exposed to new and additional costs and risks. Accordingly, the retirement of a PRO may adversely affect our financial condition and operating results. For example, in connection with our internalization of a retiring PRO, there can be no assurance that we will be able to retain such retiring PRO's employees, successfully hire new employees, or effectively integrate such employees and the retiring PRO's property management platform into our or another PRO's property management platform.

Conflicts of interest could arise with respect to certain transactions between the holders of OP units and subordinated performance units, which include our PROs, on the one hand, and us and our shareholders, on the other.

Conflicts of interest could arise with respect to the interests of holders of OP units and subordinated performance units, on the one hand, which include members of our senior management team, PROs, and trustees and us and our shareholders, on the other. Certain business combinations, the sale, disposition or transfer of certain of our assets or the repayment of certain indebtedness that may be desirable to us and our shareholders could have adverse tax consequences to such unit holders. In addition, under Maryland law, our trustees and officers have duties to the Company in connection with their management of the Company, however, under Delaware law, as a general partner, we have fiduciary duties to our operating partnership and to the limited partners in connection with the management of our operating partnership. Our duties as a general partner may come into conflict with the duties of our trustees and officers to the Company and our shareholders and we are not required to resolve such conflicts in favor of either the Company or the limited partners in our operating partnership. Further, there can be no assurance that any procedural protections we implement to address these or other conflicts of interest will result in optimal outcomes for us and our shareholders.

The partnership agreement of our operating partnership contains provisions that may delay, defer or prevent a change in control.

The partnership agreement of our operating partnership provides that subordinated performance unit holders holding more than 50% of the voting power of the subordinated performance units must approve certain change of control transactions involving us unless, as a result of such transactions, the holders of subordinated performance units are offered a choice (1) to allow their subordinated performance units to remain outstanding without the terms thereof being materially and adversely changed or the subordinated performance units are converted into or exchanged for equity securities of the surviving entity having terms and conditions that are substantially similar to those of the subordinated performance units (it being understood that we may not be the surviving entity and that the parent of the surviving entity or the surviving entity may not be publicly traded) or (2) to receive for each subordinated performance unit an amount of cash, securities or other property payable to a holder of OP units had such holder exercised its right to exchange its subordinated performance units for OP units without taking into consideration a specified conversion penalty associated with such an exchange. In addition, in the case of any such change of control transactions in which we have not received the consent of OP unit holders holding more than 50% of the OP units (other than those held by us or our subsidiaries) and of subordinated performance unit holders holding more than 50% of the voting power of the subordinated performance units (other than those held by us or our subsidiaries), such transaction is required to be approved by a company-wide vote of limited partners holding more than 50% of our outstanding OP units in which OP units (including for this purpose OP units held by us and our subsidiaries) are voted and subordinated performance units (not held by us and our subsidiaries) are voted on an applicable as converted basis and in which we will be deemed to vote the OP units held by us and our subsidiaries in proportion to the manner in which all of our outstanding common shares were voted at a shareholders meeting relating to such transaction. These approval rights could delay, deter, or prevent a transaction or a change in control that might involve a premium price for our common shares or otherwise be in the best interests of our shareholders.

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Certain provisions of the Maryland General Corporation Law (the "MGCL") and of our bylaws and our declaration of trust could inhibit a change in our control and have an adverse impact on the price of our shares.

The MGCL, our bylaws and our declaration of trust contain provisions that may discourage, delay or make more difficult a change in our control. We are subject to the Maryland Business Combination Act (the "MBCA"). Our board has adopted a resolution exempting from the MBCA any business combinations between us and (1) any other person, provided that the business combination is first approved by our board (including a majority of disinterested trustees), (2) Arlen D. Nordhagen and any of his affiliates and associates and (3) any person acting in concert with the foregoing. As a result, such persons may be able to enter into business combinations with us that may not be in the best interests of our shareholders without compliance by us with the moratorium supermajority vote requirements and other provisions of the statute. If this resolution is repealed or our board does not approve a business combination, the MBCA may discourage third parties from trying to acquire control of us and increase the difficulty of consummating such an offer.

The Maryland Control Share Acquisition Act (the "MCSAA") provides that holders of "control shares" of a Maryland real estate investment trust acquired in a "control share acquisition" have no voting rights with respect to such shares except to the extent approved by our shareholders by the affirmative vote of at least two-thirds of all the votes entitled to be cast on the matter, excluding votes entitled to be cast by the acquirer of control shares, our officers and our trustees who are also our employees. Our bylaws exempt from the MCSAA acquisitions of our shares by any person. If we amend our bylaws to repeal the exemption from MCSAA, the MCSAA also may make it more difficult for a third party to obtain control of us and increase the difficulty of consummating such an offer.

We have also adopted other measures that may make it difficult for a third party to obtain control of us, including provisions of our declaration of trust and bylaws limiting the liability of our present and former trustees and officers to us and our shareholders for money damages to the maximum extent permitted under Maryland law, requiring us to indemnify our present and former trustees and officers for actions taken in their official capacities, permitting (subject to the rights of holders of any class or series of preferred shares) removal of a trustee, with or without cause, only by the affirmative vote of at least two-thirds of the votes entitled to be cast generally in the election of trustees, and authorizing our board (without shareholder approval) to classify or reclassify our shares in one or more classes or series, to cause the issuance of additional shares and to amend our declaration of trust to increase or decrease the number of shares that we have authority to issue. These provisions, as well as other provisions of our declaration of trust and bylaws, may delay, defer or prevent a transaction or a change in control that might otherwise be in the best interests of our shareholders.

Restrictions on ownership and transfer of our shares may restrict change of control or business combination opportunities in which our shareholders might receive a premium for their shares.

In order for us to qualify as a REIT for each taxable year, no more than 50% in value of our outstanding shares may be owned, directly or constructively, by five or fewer individuals during the last half of any calendar year, and at least 100 persons must beneficially own our shares during at least 335 days of a taxable year of 12 months, or during a proportionate portion of a shorter taxable year. "Individuals" for this purpose include natural persons, private foundations, some employee benefit plans and trusts, and some charitable trusts. To assist us in preserving our REIT qualification, among other purposes, our declaration of trust generally prohibits, among other limitations, any person from beneficially or constructively owning more than 9.8% in value or in number of shares, whichever is more restrictive, of our aggregate outstanding shares of all classes and series, the outstanding shares of any class or series of our preferred shares or our outstanding common shares. These ownership limits and the other restrictions on ownership and transfer of our shares contained in our declaration of trust could have the effect of discouraging a takeover or other transaction in which holders of our common shares might receive a premium for their shares over the then prevailing market price or which holders might believe to be otherwise in their best interests. Our board of trustees has established exemptions from these ownership limits which permits certain of our institutional investors to hold up to 20% of our common shares and up to 25% of our preferred shares.

Risks Related to Our Debt Financings

There are risks associated with our indebtedness.

Our level of debt and the limitations imposed on us by our debt agreements could have significant adverse consequences, including the following:

•our cash flow may be insufficient to meet our required principal and interest payments;

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•to satisfy our debt obligations, we may be forced to dispose of one or more of our properties, possibly on disadvantageous terms;

•our debt level could place us at a competitive disadvantage compared to our competitors with less debt; and

•we may violate our restrictive covenants or otherwise default on our obligations, which may entitle our creditors to accelerate our debt obligations, foreclose on our properties securing our debt, enforce our guarantees and/or trigger default on our other indebtedness.

We depend on external sources of capital that are outside of our control, which could adversely affect our ability to acquire or develop properties, satisfy our debt obligations and/or make distributions to shareholders.

We depend on external sources of capital to acquire properties, to satisfy our debt obligations and to make distributions to our shareholders required to maintain our qualification as a REIT, and these sources of capital may not be available on favorable terms, or at all. Our access to external sources of capital depends on a number of factors, including the market's perception of our growth potential and our current and potential future earnings and our ability to continue to qualify as a REIT for U.S. federal income tax purposes. If we are unable to obtain external sources of capital, or if such capital is not available on acceptable terms, we may not be able to acquire properties when strategic opportunities exist, satisfy our debt obligations or make cash distributions to our shareholders that would permit us to qualify as a REIT or avoid paying tax on all of our net taxable income.

Increases in interest rates may increase our interest expense and adversely affect our cash flow and our ability to service our indebtedness, make cash distributions to our shareholders, and acquire or sell properties and our decision to hedge against interest rate risk might not be effective.

As of December 31, 2023, we had approximately $3.7 billion of debt outstanding, of which approximately $511.0 million, or 14.0%, is subject to variable interest rates (excluding variable-rate debt subject to interest rate swaps). If interest rates increase, our debt service obligations on variable-rate debt will increase even though the amount borrowed remains the same, while our net income, cash flows, and our ability to pay cash distributions to our shareholders correspondingly decrease. In addition, increased interest rates make the financing of any acquisition and investment activity more costly and could decrease the amount third parties are willing to pay for any properties that we wish to sell.

Although we have historically sought, and may in the future seek, to manage our exposure to interest rate volatility by using interest rate hedging arrangements, these arrangements may not be effective. Developing an effective interest rate risk strategy is complex and no strategy can completely insulate us from risks associated with interest rate fluctuations. Failure to hedge effectively against interest rate changes may adversely affect our financial condition, results of operations and ability to make cash distributions to our shareholders.

The terms and covenants relating to our indebtedness could adversely impact our economic performance.

Our credit facility, term loan facilities and senior unsecured notes contain (and any new or amended facility we may enter into from time to time will likely contain) customary affirmative and negative covenants, including financial covenants that, among other things, cap our total leverage and our unsecured debt. In the event that we fail to satisfy our covenants, we would be in default under our debt agreements and may be required to repay such debt with capital from other sources. Under such circumstances, other sources of debt or equity capital may not be available to us, or may be available only on unattractive terms. Moreover, the presence of such covenants could cause us to operate our business with a view toward compliance with such covenants, which might not produce optimal returns for shareholders.

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Risks Related to Our Qualification as a REIT

Our failure to remain qualified as a REIT would subject us to U.S. federal income tax and applicable state and local taxes, which would reduce the amount of operating cash flow to our shareholders.

We have elected and we believe that we have qualified to be taxed as a REIT commencing with our taxable year ended December 31, 2015. We have not requested, and do not intend to request a ruling from the Internal Revenue Service ("IRS"), that we qualify as a REIT. Qualification as a REIT involves the application of highly technical and complex Code provisions and Treasury Regulations promulgated thereunder for which there are limited judicial and administrative interpretations. To qualify as a REIT, we must meet, on an ongoing basis through actual operating results, various tests regarding the nature and diversification of our assets and our income, the ownership of our outstanding shares and the amount of our distributions. Our ability to satisfy these asset tests depends upon our analysis of the characterization and fair market values of our assets, some of which are not susceptible to a precise determination, and for which we will not obtain independent appraisals. Moreover, new legislation, court decisions or administrative guidance may, in each case possibly with retroactive effect, make it more difficult or impossible for us to qualify as a REIT. Thus, while we believe that we have been organized and operated and we intend to operate so that we will continue to qualify as a REIT, given the highly complex nature of the rules governing REITs, the ongoing importance of factual determinations and the possibility of future changes in our circumstances, no assurance can be given that we have qualified or will so qualify for any particular year. These considerations also might restrict the types of assets that we can acquire or services that we can provide in the future.

We own and may in the future acquire direct or indirect interests in entities that have elected or will elect to be treated as REITs under the Code (each a "Subsidiary REIT"). If a Subsidiary REIT were to fail to qualify as a REIT, then (i) that Subsidiary REIT would become subject to U.S. federal income tax, (ii) shares in such Subsidiary REIT would cease to be qualifying assets for purposes of the asset tests applicable to REITs, and (iii) it is possible that we would fail certain of the tests applicable to REITs, in which event we would fail to qualify as a REIT unless we qualify for certain statutory relief provisions.

In addition, in order to qualify as a REIT, prior to the end of the taxable year, we must also distribute any earnings and profits of any property we acquire in certain tax-deferred transactions to the extent such earnings accrued at a time when such corporation did not qualify as a REIT. We have entered into certain transactions involving the tax-deferred acquisition of target corporations. We believe that we have distributed any earnings and profits of such target corporations attributable to any period that such corporations did not qualify as a REIT. However, no assurances can be provided in this regard, and if there is a determination that we have inherited and retained any such earnings and profits, our qualification as a REIT could be adversely impacted.

If we fail to qualify as a REIT in any taxable year, and we do not qualify for certain statutory relief provisions, we would be required to pay U.S. federal income tax on our taxable income at regular corporate rates, and distributions to our shareholders would not be deductible by us in determining our taxable income. In such a case, we might need to borrow money, sell assets, or reduce or even cease making distributions in order to pay our taxes. Our payment of income tax would reduce significantly the amount of operating cash flow to our shareholders. Furthermore, if we fail to maintain our qualification as a REIT, we no longer would be required to make distributions to our shareholders. In addition, unless we were eligible for certain statutory relief provisions, we could not re-elect to be taxed as a REIT until the fifth calendar year following the year in which we failed to qualify.

Even if we qualify as a REIT, we may face other tax liabilities that reduce our cash flow.

Even if we qualify for taxation as a REIT, we may be subject to certain U.S. federal, state and local taxes on our income and assets, including taxes on any undistributed income, state or local income and property and transfer taxes, including real property transfer taxes. In addition, we could, in certain circumstances, be required to pay an excise or penalty tax (which could be significant in amount) in order to utilize one or more relief provisions under the Code to maintain our qualification as a REIT. Any of these taxes would decrease operating cash flow to our shareholders.

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In order to qualify as a REIT, we must distribute to our shareholders each calendar year at least 90% of our net taxable income (excluding net capital gain). To the extent that we satisfy the 90% distribution requirement, but distribute less than 100% of our net taxable income (including net capital gain), we would be subject to U.S. federal corporate income tax on our undistributed net taxable income. In addition, we will incur a 4% non-deductible excise tax on the amount, if any, by which our distributions in any calendar year are less than a minimum amount specified under U.S. federal income tax laws. Although we intend to distribute our net taxable income to our shareholders in a manner that would avoid this 4% tax, there can be no assurance that we will be able to do so, due to timing differences between our actual receipt of cash and the inclusion of items in our income for U.S. federal income tax purposes, the effect of non-deductible capital expenditures, or the creation of reserves or required debt or amortization payments.

In addition, we will be subject to a 100% tax on any income from sales or other dispositions of property (other than property treated as foreclosure property under the Code) that is held as inventory or primarily for sale to customers in the ordinary course of a trade or business by a REIT, either directly or indirectly through certain pass-through subsidiaries (a "prohibited transaction"). In order to meet the REIT qualification requirements, or to avoid the imposition of the penalty tax on prohibited transactions, we may hold some of our assets or provide certain services to our tenants through one or more TRSs, which generally will be subject to U.S. federal, state and local corporate taxes. In addition, if a REIT lends money to a TRS, the TRS may be unable to deduct all or a portion of the interest paid to the REIT, which could increase the tax liability of the TRS. In addition, the Code imposes a 100% tax on certain transactions between a TRS and its parent REIT that are not conducted on an arm's length basis. We intend to structure transactions with any TRS on terms that we believe are arm's length to avoid incurring the 100% excise tax described above. There can be no assurances, however, that we will be able to avoid application of the 100% tax. Furthermore, if we acquire appreciated assets from a corporation that is or has been a subchapter C corporation in a transaction in which the adjusted tax basis of such assets in our hands is less than the fair market value of the assets, determined at the time we acquired such assets, and if we subsequently dispose of any such assets during the 5-year period following the acquisition of the assets from the C corporation, we will be subject to tax at the highest corporate tax rates on any gain from the disposition of such assets to the extent of the excess of the fair market value of the assets on the date that we acquired such assets over the basis of such assets on such date, which we refer to as built-in gains. In addition, we have entered into certain transactions in which we acquired target entities in tax-deferred transactions. To the extent such entities had outstanding U.S. federal income tax or other tax liabilities, we would succeed to such liabilities. Payment of these taxes generally could materially and adversely affect our income, cash flow, results of operations, financial condition, liquidity and prospects, and could adversely affect the value of our common shares and our ability to make distributions to our shareholders.

Complying with the REIT requirements may cause us to forgo and/or liquidate otherwise attractive investments, and in some situations, to maintain our REIT qualification, we may be forced to borrow funds during unfavorable market conditions.

To qualify as a REIT, we must ensure that at least 75% of our gross income for each taxable year, excluding certain amounts, is derived from certain real property-related sources, and at least 95% of our gross income for each taxable year, excluding certain amounts, is derived from certain real property-related sources and passive income such as dividends and interest. In addition, we must ensure that, at the end of each calendar quarter, at least 75% of the value of our total assets consists of cash, cash items, U.S. government securities and qualified real estate assets. The remainder of our investment in securities generally cannot include more than 10% of the outstanding voting securities of any one issuer (other than U.S. government securities, securities of corporations that are treated as TRSs and qualified real estate assets) or more than 10% of the total value of the outstanding securities of any one issuer (other than government securities, securities of corporations that are treated as TRSs and qualified real estate assets). In addition, in general, no more than 5% of the value of our assets can consist of the securities of any one issuer (other than U.S. government securities, securities of corporations that are treated as TRSs and qualified real estate assets), no more than 20% of the value of our total assets can be represented by securities of one or more TRSs and no more than 25% of the value of our assets can consist of debt instruments issued by publicly offered REITs that are not otherwise secured by real property. If we fail to comply with these asset requirements at the end of any calendar quarter, we must correct the failure within 30 days after the end of the calendar quarter or qualify for certain statutory relief provisions to avoid losing our REIT qualification and suffering adverse tax consequences.

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To meet these tests, we may be required to take or forgo taking actions that we would otherwise consider advantageous. For instance, in order to satisfy the gross income or asset tests applicable to REITs under the Code, we may be required to forgo investments that we otherwise would make, and we may be required to liquidate from our portfolio otherwise attractive investments. In addition, we may be required to make distributions to shareholders at disadvantageous times or when we do not have funds readily available for distribution. As a result, we may need to borrow funds to meet the REIT distribution requirements even if the then prevailing market conditions are not favorable for these borrowings. Our access to third-party sources of capital depends on a number of factors, including the market's perception of our growth potential, our current debt levels, the per share trading price of our common shares, and our current and potential future earnings. We cannot assure you that we will have access to such capital on favorable terms at the desired times, or at all, which may cause us to curtail our investment activities and/or to dispose of assets at inopportune times. These actions could reduce our income and amounts available for distribution to our shareholders. Thus, compliance with the REIT requirements may hinder our investment performance.

If our operating partnership is treated as a corporation for U.S. federal income tax purposes, we will cease to qualify as a REIT.

We believe our operating partnership qualifies as a partnership for U.S. federal income tax purposes, and accordingly generally will not be subject to U.S. federal income tax on its income. Instead, each of its partners, including us, will be required to pay tax on its allocable share of our operating partnership's income. No assurance can be provided, however, that the IRS will not challenge our operating partnership's status as a partnership for U.S. federal income tax purposes, or that a court would not sustain such a challenge. If the IRS were successful in treating our operating partnership as a corporation for U.S. federal income tax purposes, we would fail to meet the gross income tests and certain of the asset tests applicable to REITs, we would cease to qualify as a REIT, and both we and our operating partnership would become subject to U.S. federal, state and local income tax. The payment by our operating partnership of income tax would reduce significantly the amount of cash available to our operating partnership to satisfy obligations to make principal and interest payments on its debt and to make distribution to its partners, including us.

Complying with REIT requirements may limit our ability to hedge effectively and may cause us to incur tax liabilities.

The REIT provisions of the Code may limit our ability to hedge our assets and operations. Under these provisions, any income that we generate from transactions intended to hedge our interest rate risk will be excluded from gross income for purposes of the REIT 75% and 95% gross income tests if (i) the instrument (a) hedges interest rate risk on liabilities used to carry or acquire real estate assets or (b) hedges an instrument described in clause (a) for a period following the extinguishment of the liability or the disposition of the asset that was previously hedged by the hedged instrument, and (ii) the relevant instrument is properly identified under applicable Treasury regulations. Income from hedging transactions that does not meet these requirements will generally constitute non-qualifying income for purposes of both the REIT 75% and 95% gross income tests. As a result of these rules, we may have to limit our use of hedging techniques that might otherwise be advantageous or implement those hedges through a TRS. This could increase the cost of our hedging activities because our TRS would be subject to tax on gains or expose us to greater risks associated with changes in interest rates than we would otherwise want to bear, and we generally would not benefit from losses in our TRS, although, subject to limitation, such losses may be carried forward to offset future taxable income of the TRS.

The ability of our board of trustees to revoke our REIT election without shareholder approval may cause adverse consequences to our shareholders.

Our declaration of trust provides that the board of trustees may revoke or otherwise terminate our REIT election, without the approval of our shareholders, if the board determines that it is no longer in our best interest to attempt to, or continue to, qualify as a REIT. If we cease to qualify as a REIT, we would become subject to U.S. federal income tax on our net taxable income and we generally would no longer be required to distribute any of our net taxable income to our shareholders, which may have adverse consequences on our total return to our shareholders.

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Legislative or regulatory tax changes related to REITs could materially and adversely affect our business.

At any time, the U.S. federal income tax laws or regulations governing REITs or the administrative interpretations of those laws or regulations may be changed, possibly with retroactive effect. We cannot predict if or when any new U.S. federal income tax law, regulation or administrative interpretation, or any amendment to any existing U.S. federal income tax law, regulation or administrative interpretation, will be adopted, promulgated or become effective or whether any such law, regulation or interpretation may take effect retroactively. We and our shareholders could be adversely affected by any such change in, or any new, U.S. federal income tax law, regulation or administrative interpretation. Stockholders are urged to consult with their tax advisors regarding the effects of the other legislative, regulatory or administrative developments on an investment in the Company's common stock.

Risks Related to Our Common Shares and Preferred Shares

Common shares and preferred shares eligible for future sale may have adverse effects on our share price.

Subject to applicable law and the rules of any stock exchange on which our shares may be listed or traded, our board, without common shareholder approval, may authorize us to issue additional authorized and unissued common shares and preferred shares on the terms and for the consideration it deems appropriate and may amend our declaration of trust to increase the total number of shares, or the number of shares of any class or series, that we are authorized to issue. In addition, our operating partnership may issue OP units, which are redeemable for cash or, at our option exchangeable on a one-for-one basis into common shares after an agreed period of time and certain other conditions, preferred units of limited partnership interest, which are redeemable for cash or, at our option exchangeable on a one-for-one basis into our 6.000% Series A cumulative redeemable preferred shares of beneficial interest ("Series A Preferred Shares") and subordinated performance units, which are only convertible into OP units beginning two years following the initial issuance of the applicable series and then (i) at the holder's election only upon the achievement of certain performance thresholds relating to the properties to which such subordinated performance units relate or (ii) at our election upon a retirement event of a PRO that holds such subordinated performance units or upon certain qualifying terminations.

Notwithstanding the two-year lock out period on conversions of subordinated performance units into OP units, if such subordinated performance units were convertible into OP units as of December 31, 2023, each subordinated performance unit would on average hypothetically convert into 1.55 OP units, or into an aggregate of approximately 18.8 million OP units. These amounts are based on historical financial information for the trailing twelve months ended December 31, 2023. The hypothetical conversion is calculated by dividing the average cash available for distribution, or CAD, per subordinated performance unit by 110% of the CAD per OP unit over the same period. We anticipate that as our CAD grows over time, the conversion ratio will also grow, including to levels that may exceed this amount. The actual number of OP units into which such subordinated performance units will become convertible may vary significantly and will depend upon the applicable conversion penalty and the actual CAD to the OP units and the actual CAD to the converted subordinated performance units in the one-year period ending prior to conversion. We have also granted registration rights to those persons who will be eligible to receive common shares issuable upon exchange of OP units and preferred shares issuable upon exchange of preferred units issued in our contribution transactions.

We cannot predict the effect, if any, of future sales of our common or preferred shares or the availability of shares for future sales, on the market price of our common or preferred shares. The market price of our common shares may decline significantly when the restrictions on resale by certain of our shareholders lapse. Sales of substantial amounts of common or preferred shares or the perception that such sales could occur may adversely affect the prevailing market price for our common shares.

We cannot assure our ability to pay dividends in the future.

Historically, we have paid quarterly common share dividends to our shareholders and quarterly distributions to our operating partnership unitholders, and we intend to continue to pay such dividends and distributions in amounts such that all or substantially all of our net taxable income in each year is distributed, which, along with other factors, should enable us to continue to qualify for the tax benefits accorded to a REIT under the Code. We have not established a minimum dividends payment level, and all future distributions will be made at the discretion of our board. Our ability to pay dividends will depend upon, among other factors:

•the operational and financial performance of our properties;

•capital expenditures with respect to existing and newly acquired properties;

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•general and administrative expenses associated with our operation as a publicly-held REIT;

•maintenance of our REIT qualification;

•the amount of, and the interest rates on, our debt and the ability to refinance our debt;

•the absence of significant expenditures relating to environmental and other regulatory matters; and

•other risk factors described in this Annual Report on Form 10-K.

Certain of these matters are beyond our control and any significant difference between our expectations and actual results could have a material adverse effect on our cash flow and our ability to make distributions to shareholders.

Future offerings of debt or equity securities, which may rank senior to our common shares, may adversely affect the market price of our common shares.

If we decide to issue debt securities in the future, which would rank senior to our common shares, it is likely that they will be governed by an indenture or other instrument containing covenants restricting our operating flexibility. Additionally, any equity securities or convertible or exchangeable securities that we issue in the future may have rights, preferences and privileges more favorable than those of our common shares and may result in dilution to owners of such shares. We and, indirectly, our shareholders will bear the cost of issuing and servicing such securities. Because our decision to issue debt or equity securities in any future offering will depend on market conditions and other factors beyond our control, we cannot predict or estimate the amount, timing or nature of our future offerings. Thus, holders of our common shares will bear the risk of our future offerings reducing the market price of our shares and diluting the value of their common share holdings in us.

Item 1B. Unresolved Staff Comments

None.

Item 1C. Cybersecurity

Risk management and strategy

We recognize the critical importance of developing, implementing, and maintaining robust cybersecurity measures aligned to industry standards to safeguard our information systems and protect the confidentiality, integrity, and availability of our data.

Management of Material Risks & Integration into Overall Risk Management

We have strategically integrated cybersecurity risk management into our broader risk management framework to promote a company-wide culture of cybersecurity awareness and risk management and have incorporated cybersecurity considerations into our decision-making processes. Our risk management team works closely with our IT department to identify, evaluate and address cybersecurity risks in alignment with our business objectives and operational needs. Our risk management team also provides regular reporting to management on our enterprise cybersecurity risk posture.

Engagement of Third-parties on Risk Management

Recognizing the complexity and evolving nature of cybersecurity threats, we engage a range of external experts, including cybersecurity assessors and consultants in evaluating and testing our risk management systems. These partnerships enable us to leverage specialized knowledge and insights, so that we can better understand the current and evolving cybersecurity risks and strategies. Our collaboration with these third-parties includes periodic audits, threat assessments, and consultation on security enhancements.

Risks from Cybersecurity Threats

We are not aware of any risks from cybersecurity threats, including as a result of any cybersecurity incidents, which have materially affected or are reasonably likely to materially affect our Company, including our business strategy, results of operations, or financial condition. Refer to “Item 1A. Risk factors” in this annual report on Form 10-K, including “Security breaches through cyber-attacks, cyber-intrusions, or other methods could disrupt our information technology networks and related systems”, for additional discussion about cybersecurity-related risks.

Governance

The board of trustees is acutely aware of the critical nature of managing risks associated with cybersecurity threats and oversees the Company's cybersecurity risk management activities.

Board of Trustees Oversight

The audit committee of our board of trustees is central to the board of trustees’s oversight of cybersecurity risks and bears the primary responsibility for this domain. The members of the audit committee have a variety of expertise, including financial, regulatory and risk management. The audit committee reviews our policies with respect to risk assessment and risk management related to cybersecurity. The audit committee and the board of trustees receive updates on the Company’s cybersecurity risks and initiatives periodically. In addition, cybersecurity matters are reported to the audit committee or board of trustees so that the board of trustees and audit committee can effectively carry out their oversight role.

Management’s Role Managing Risk

Our risk management committee is comprised of a cross section of the Company’s management team. The risk management committee has identified cybersecurity as a key risk to the Company’s operations and established a cybersecurity sub-committee, which is comprised of members of the risk management committee and other personnel, to focus on this key risk.

The cybersecurity sub-committee plays a pivotal role in informing the risk management committee on cybersecurity risks. They provide comprehensive briefings to the risk management committee on a regular basis. These briefings encompass a broad range of topics, including:

•Awareness of cybersecurity landscape, emerging threats, trends and developments;

•Status of ongoing cybersecurity initiatives and strategies;

•Incident reports and learnings from any cybersecurity events;

•Compliance with regulatory requirements and industry standards; and

•Education in cybersecurity and associated risk management frameworks.

The risk management committee actively participates in strategic decisions related to cybersecurity, offering guidance and approval for major initiatives. This involvement ensures that cybersecurity considerations are a consistent focus of the Company and that the Company's cybersecurity efforts are aligned with the overall risk management framework. We have also implemented cybersecurity training at all levels of our organization and conduct periodic phishing assessment for our employees to reinforce that training.

Risk Management Personnel

Primary responsibility for assessing, monitoring and managing our cybersecurity risks rests with the cybersecurity sub-committee. With over a combined 45 years of experience in the field of cybersecurity, the cybersecurity sub-committee brings a wealth of expertise to their role. Their in-depth knowledge and experience are instrumental in developing and executing our cybersecurity strategies. Our cybersecurity sub-committee oversees our cybersecurity strategies, tests our compliance with standards, remediates known risks, and leads our employee training program.

Monitor Cybersecurity Incidents

The cybersecurity sub-committee stays apprised about the latest developments in cybersecurity, including potential threats and innovative risk management techniques, which is important for the effective prevention, detection, mitigation, and remediation of cybersecurity incidents. The cybersecurity sub-committee implements and oversees processes for the regular monitoring of our information systems. This includes the deployment of advanced security measures and regular system audits to identify potential vulnerabilities. In the event of a cybersecurity incident, the cybersecurity sub-committee is equipped with a well-defined incident response plan, which provides a framework to mitigate the impact of cybersecurity incidents

The cybersecurity sub-committee regularly informs the risk management committee of matters related to cybersecurity risks and incidents. This ensures that the highest levels of management are kept abreast of the cybersecurity posture and potential risks facing the Company. Furthermore, significant cybersecurity matters, and strategic risk management decisions are escalated to the board of trustees, ensuring that they have comprehensive oversight and can provide guidance on critical cybersecurity issues.

Item 2. Properties

As of December 31, 2023, we held ownership interests in and operated a geographically diversified portfolio of 1,050 self storage properties located in 42 states and Puerto Rico, comprising approximately 68.6 million rentable square feet, configured in approximately 542,000 storage units, which excludes 39 self storage properties classified as held for sale to be sold to a third party in 2024. Of these properties, we reported 809 wholly-owned self storage properties on a consolidated basis that contain approximately 51.9 million rentable square feet, which excludes an additional 56 self storage properties classified as held for sale that were contributed to the 2024 Joint Venture, and we held a 25% ownership interest in 185 unconsolidated real estate venture properties that contain approximately 13.5 million rentable square feet.

The following table sets forth summary information regarding our consolidated properties by state as of December 31, 2023.


	Number of	Number of	Rentable	% of Rentable		Period-end
State/Territory	Properties	Units	Square Feet	Square Feet		Occupancy
Texas	172	79,045	10,986,692	21.2	%	87.3	%
California(1)	87	52,410	6,629,212	12.8	%	84.8	%
Florida	76	43,946	4,975,310	9.6	%	85.7	%
Oregon	70	29,217	3,657,543	7.0	%	84.0	%
Georgia	50	22,173	3,022,988	5.8	%	81.8	%
Arizona	34	18,858	2,175,802	4.2	%	84.2	%
North Carolina	34	16,758	2,097,487	4.0	%	85.6	%
Oklahoma	33	15,300	2,143,482	4.1	%	86.2	%
Louisiana(1)	25	11,450	1,388,385	2.7	%	83.7	%
Pennsylvania	22	10,435	1,296,060	2.5	%	87.1	%
Colorado	22	9,488	1,197,510	2.3	%	85.3	%
Washington	19	6,633	871,169	1.7	%	82.7	%
Puerto Rico	15	12,852	1,388,637	2.7	%	92.9	%
Nevada	15	7,557	962,182	1.9	%	86.8	%
New Hampshire	15	7,117	888,611	1.7	%	89.7	%
Kansas	14	4,924	670,702	1.3	%	88.0	%
Indiana	12	6,533	828,453	1.6	%	83.6	%
Alabama	11	6,036	907,914	1.7	%	77.8	%
New Mexico	10	5,500	716,307	1.4	%	86.8	%
Maryland	8	4,564	493,184	1.0	%	86.6	%
Massachusetts	7	5,014	538,005	1.0	%	82.1	%
Illinois	6	4,227	425,361	0.8	%	82.2	%
Tennessee	5	2,550	349,663	0.7	%	87.4	%
Kentucky	5	2,784	412,051	0.8	%	78.7	%
New Jersey	5	2,743	352,338	0.7	%	84.5	%
Idaho	5	1,454	271,511	0.5	%	83.8	%
Arkansas	5	2,604	401,820	0.8	%	78.4	%
South Carolina	4	2,059	254,853	0.5	%	83.9	%
Minnesota	4	1,198	192,770	0.4	%	83.7	%
Missouri	3	1,244	153,606	0.3	%	90.0	%
Virginia	3	1,382	174,915	0.3	%	83.8	%
Iowa	3	3,100	414,442	0.8	%	74.6	%
Connecticut	3	1,182	141,090	0.3	%	82.1	%
New York	2	1,713	174,591	0.3	%	81.3	%
Ohio	1	951	112,555	0.2	%	84.8	%
Montana	1	438	60,250	0.1	%	95.5	%
Wyoming	1	424	56,500	0.1	%	85.7	%
Wisconsin	1	378	59,672	0.1	%	85.1	%
Utah	1	312	46,500	0.1	%	87.7	%
Total/Weighted Average(2)	809	406,553	51,890,123	100.0	%	85.3	%

(1) Six of the California properties and one of the Louisiana properties are subject to non-cancelable leasehold interest agreements that are classified as operating leases. See "Note 13. Leases" in Item 8. "Financial Statements and Supplementary Data."
(2) Excludes self storage properties classified as held for sale consisting of (i) 39 self storage properties, comprising approximately 2.4 million rentable square feet, configured in approximately 18,000 storage units to be sold to a third party in 2024 and (ii) 56 self storage properties, comprising approximately 3.2 million rentable square feet, configured in approximately 24,000 storage units that were contributed to the 2024 Joint Venture in 2024.

The following table sets forth summary information regarding our unconsolidated real estate venture properties by state as of December 31, 2023.


	Number of	Number of	Rentable	% of Rentable		Period-end
State	Properties	Units	Square Feet	Square Feet		Occupancy
Florida	27	15,032	1,716,479	12.7	%	82.4	%
Michigan	25	15,930	2,017,998	15.0	%	86.7	%
New Jersey	15	10,789	1,253,588	9.3	%	84.7	%
Alabama	14	5,517	825,238	6.1	%	86.4	%
Ohio	14	9,375	1,124,347	8.3	%	84.7	%
California	12	6,648	779,342	5.8	%	85.5	%
Georgia	11	6,132	872,058	6.5	%	84.2	%
Texas	11	9,113	997,098	7.4	%	89.4	%
Other(1)	56	32,592	3,906,901	28.9	%	84.9	%
Total	185	111,128	13,493,049	100.0	%	85.2	%

(1) Other states in the unconsolidated real estate ventures include Arizona, Delaware, Illinois, Massachusetts, Minnesota, Mississippi, Nevada, New York, Oklahoma, Pennsylvania, Rhode Island, Tennessee and Virginia.

Our portfolio consists of self storage properties that are designed to offer customers convenient, affordable, and secure storage units. Generally, our properties are in highly visible locations clustered in states or markets with strong population and job growth and are specifically designed to accommodate residential and commercial tenants with features such as security systems, electronic gate entry, easy access, climate control, and pest control. Our units typically range from 25 square feet to 300 square feet, and some of our properties also offer outside storage for vehicles, boats, and equipment. We provide 24-hour access to many storage units through computer controlled access systems, as well as alarm and sprinkler systems on many of our individual storage units. Almost all of the storage units in our portfolio are leased on a month-to-month basis providing us the flexibility to increase rental rates over time as market conditions permit. Additional information on our consolidated self storage properties is contained in "Schedule III - Real Estate and Accumulated Depreciation" in this Annual Report on Form 10-K.

Item 3. Legal Proceedings

We are not currently subject to any legal proceedings that we consider to be material.

Item 4. Mine Safety Disclosures

Not applicable.

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PART II

Item 5. Market for the Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Market Information

Our common shares have been listed and traded on the NYSE under the symbol "NSA" since April 22, 2015. Prior to that time there was no public market for our common shares.

Holders

As of February 26, 2024, the Company had 83 record holders of its common shares. The 83 holders of record do not include the beneficial owners of common shares whose shares are held by a broker or bank. Such information was obtained from our transfer agent and registrar.

Dividends

Since our initial quarter as a publicly-traded REIT, we have made regular quarterly distributions to our shareholders. Holders of common shares are entitled to receive distributions when declared by our board of trustees out of any assets legally available for that purpose. In order to maintain our status as a REIT for U.S. federal income tax purposes, we are required to distribute at least 90% of our "REIT taxable income," which is generally equivalent to our net taxable ordinary income, determined without regard to the deduction for dividends paid and excluding net capital gains to our shareholders annually.

Common share dividends are characterized for U.S. federal income tax purposes as ordinary income, capital gains, return of capital or a combination thereof. Each year we communicate to shareholders the tax characterization of the common share dividends paid during the preceding year. Our tax return for the year ended December 31, 2023 has not yet been filed and consequently, the taxability information presented for our dividends paid in 2023 is based upon management's estimate. The following table summarizes the taxability of our dividends per common share for the year ended December 31, 2023:


	Year Ended
	December 31, 2023
Ordinary Income	$	1.653434	74.2	%
Capital Gain	0.239048		10.7	%
Return of Capital	0.337518		15.1	%
Total	$	2.230000	100.0	%

Equity Compensation Plan Information

Information about our equity compensation plans is incorporated by reference to Item 12 of Part III of this Annual Report on Form 10-K.

Unregistered Sales of Equity Securities

During the three months ended December 31, 2023, the Company, in its capacity as general partner of its operating partnership, caused the operating partnership to issue 186,003 common shares to satisfy redemption requests from certain limited partners.

On October 6, 2023, the operating partnership issued 179,354 Series A-1 preferred units to affiliates of Optivest, one of the Company's existing PROs, as partial consideration for the acquisition of a self storage property. In addition, 7,600 LTIP units that were previously granted to Optivest and an affiliate of Optivest vested in connection with this transaction.

On October 24, 2023, the operating partnership issued 35,446 Series SO subordinated performance units to affiliates of Southern, one of the Company's existing PROs, in exchange for cash in connection with the acquisition of a self storage property from an unrelated third party.

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Following a specified lock up period after the date of issuance set forth above, the OP units issued by the operating partnership may be redeemed from time to time by holders for a cash amount per OP unit equal to the market value of an equivalent number of common shares. The Company has the right, but not the obligation, to assume and satisfy the redemption obligation of the operating partnership described above by issuing one common share in exchange for each OP unit tendered for redemption.

The Company has elected to report early the private placement of its common shares that may occur if the Company elects to assume the redemption obligation of the operating partnership as described above in the event that OP units are in the future tendered for redemption.

Following a two-year lock-up period, holders of subordinated performance units may elect, only upon the achievement of certain performance thresholds relating to the properties to which such subordinated performance units relate, to convert all or a portion of such subordinated performance units into OP units one time each year by submitting a completed conversion notice prior to December 1 of such year. All duly submitted conversion notices will become effective on the immediately following January 1. For additional information about the conversion or exchange of subordinated performance units into OP units, see Note 9 in Item 8 of this report.

As of February 26, 2024, other than those OP units held by the Company, 40,514,212 OP units were outstanding (including 787,284 outstanding Long-Term Incentive Plan Units ("LTIP units") and 2,120,491 outstanding OP units in certain consolidated subsidiaries of the operating partnership ("DownREIT OP units"), which are convertible into, or exchangeable for, OP units on a one-for-one basis, subject to certain conditions).

These issuances were exempt from registration under Section 4(a)(2) of the Securities Act of 1933, as amended.

Issuer Purchases of Equity Securities

On July 11, 2022, the Company approved a share repurchase program authorizing the repurchase of up to $400.0 million of the Company's common shares, under which $256,892 of commons shares remain available for repurchase. On December 1, 2023, the Company approved a new share repurchase program authorizing, but not obligating, the repurchase of up to $275.0 million of the Company's common shares. The table below summarizes all of our repurchases of common shares during three months ended December 31, 2023:


Period	Total number of shares purchased	Average Price Paid Per Share		Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs	Approximate Dollar Value of Shares that May Yet be Purchased under the Plans or Programs
October 1 - October 31, 2023	—	$	—	—	$	27,591,757
November 1 - November 30, 2023	852,771	32.05		852,771	256,892
December 1 - December 31, 2023	—	—		—	275,256,892
Total/Weighted Average	852,771	$	32.05	852,771	$	275,256,892

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Performance Graph

The following chart compares the yearly cumulative total shareholder return for our common shares with the cumulative shareholder return of companies on (i) the S&P 500 Index, (ii) the Russell 2000 and (iii) the Nareit All Equity REIT Index as provided by Nareit for the period beginning December 31, 2018 and ending December 31, 2023.


	Period Ending
Index	12/31/2018		12/31/2019		12/31/2020		12/31/2021		12/31/2022		12/31/2023
National Storage Affiliates Trust	$	100	$	132	$	148	$	293	$	160	$	195
S&P 500	100		131		156		200		164		207
Russell 2000	100		126		151		173		138		161
Nareit All Equity REIT Index	100		129		122		172		129		144

The foregoing item assumes $100.00 invested on December 31, 2018, with dividends reinvested. The Performance Graph will not be deemed to be incorporated by reference into any filing by NSA under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except to the extent that NSA specifically incorporates the same by reference.

Item 6. [Reserved]

None.

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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with the financial statements and notes thereto included in Item 8. "Financial Statements and Supplementary Data" as well as Item 1. "Business," Item 1A. "Risk Factors," and Item 2. "Properties," respectively, in this Annual Report on Form 10-K.

Overview

Our vice chairperson of the board of trustees and former chief executive officer, Arlen D. Nordhagen, co-founded SecurCare Self Storage, Inc. in 1988 to invest in and manage self storage properties. While growing SecurCare to over 150 self storage properties, Mr. Nordhagen recognized a market opportunity for a differentiated public self storage REIT that would leverage the benefits of national scale by integrating multiple experienced regional self storage operators with local operational focus and expertise. We believe that his vision, which is the foundation of the Company, aligns the interests of our PROs, with those of our public shareholders by allowing our PROs to participate alongside our shareholders in our financial performance and the performance of our PROs' managed portfolios. Our PRO structure offers our PROs a unique opportunity to serve as regional property managers for their managed portfolios and directly participate in the potential upside of those properties while simultaneously diversifying their investment to include a broader portfolio of self storage properties. Over time, largely through our unconsolidated real estate ventures and internalization of three of our largest PROs, SecurCare, Northwest and Move It, we have developed a full service internally-staffed property management platform to complement our PRO structure.

Our Structure

Through our property management platform, we direct, manage and control the day-to-day operations and affairs of certain consolidated properties and our unconsolidated real estate ventures under our iStorage, Northwest, SecurCare and Move It brands. As of December 31, 2023, our property management platform managed and controlled 532 of our consolidated properties and 185 of our unconsolidated real estate venture properties, which excludes 39 consolidated properties classified as held for sale to be sold to a third party in 2024. As of December 31, 2023, our PROs managed the day-to-day operations of 333 of our consolidated properties.

For properties managed by our PROs, our structure promotes operator accountability as subordinated performance units issued to our PROs in exchange for the contribution of their properties are entitled to distributions only after those properties satisfy minimum performance thresholds. In the event of a material reduction in operating cash flow, distributions on our subordinated performance units will be reduced before or disproportionately to distributions on our common shares held by our common shareholders. In addition, we expect our PROs will generally co-invest subordinated equity in the form of subordinated performance units in each acquisition that they source, and the value of these subordinated performance units will fluctuate with the performance of their managed portfolios. Therefore, our PROs are incentivized to select acquisitions that are expected to exceed minimum performance thresholds, thereby increasing the value of their subordinated equity stake. We expect that our shareholders will benefit from the higher levels of property performance that our PROs are incentivized to deliver.

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Our PROs

We had eight PROs as of December 31, 2023: Optivest, Guardian, Southern, Blue Sky, Moove In, Hide Away, Storage Solutions and Personal Mini. We seek to further expand our platform by continuing to recruit additional established self storage operators, while integrating our operations through the implementation of centralized initiatives, including management information systems, revenue enhancement, and cost optimization programs. Our national platform allows us to capture cost savings by eliminating redundancies and utilizing economies of scale across the property management platforms of our PROs while also providing greater access to lower-cost capital.

Effective January 1, 2023, Move It Self Storage and its controlled affiliates, elected to retire as one our PROs. As a result of the retirement, on January 1, 2023, management of our properties in the Move It managed portfolio was transferred to us and the Move It brand name and related intellectual property was internalized by us, and we discontinued payment of any supervisory and administrative fees or reimbursements to Move It.

Our Consolidated Properties

As of December 31, 2023, we owned a geographically diversified portfolio of 809 self storage properties, located in 38 states and Puerto Rico, comprising approximately 51.9 million rentable square feet, configured in approximately 407,000 storage units, which excludes self storage properties classified as held for sale consisting of (i) 39 self storage properties located in eight states, comprising approximately 2.4 million rentable square feet, configured in approximately 18,000 storage units to be sold to a third party in 2024 and (ii) 56 self storage properties located in seven states, comprising approximately 3.2 million rentable square feet, configured in approximately 24,000 storage units that were contributed to the 2024 Joint Venture in 2024. Of these properties, 306 were acquired by us from our PROs, 502 were acquired by us from third-party sellers and one was acquired by us from the 2016 Joint Venture.

Our Unconsolidated Real Estate Ventures

2024 Joint Venture

2023 Joint Venture

As of December 31, 2023, our 2023 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8), in which we have a 25% ownership interest, did not own or operate any self storage properties. The agreement allows for equity capital contributions of up to $400 million from the 2023 JV Members over a 24-month period starting in December 2023, with options to extend the investment time period by two additional six-month periods.

2018 Joint Venture

As of December 31, 2023, our 2018 Joint Venture, in which we have a 25% interest, owned and operated a portfolio of 104 properties containing approximately 7.8 million rentable square feet, configured in approximately 64,000 storage units and located across 17 states.

2016 Joint Venture

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As of December 31, 2023, our 2016 Joint Venture, in which we have a 25% ownership interest, owned and operated a portfolio of 81 properties containing approximately 5.7 million rentable square feet, configured in approximately 47,000 storage units and located across 13 states.

Results of Operations

When reviewing our results of operations it is important to consider the timing of acquisition and disposition activity. We acquired 20 self storage properties and annexes to existing properties during the year ended December 31, 2023 and 45 self storage properties during the year ended December 31, 2022. We disposed of 32 self storage properties and classified self storage properties as held for sale consisting of (i) 39 self storage properties to be sold to a third party in 2024 and (ii) 56 self storage properties that were contributed to the 2024 Joint Venture in 2024, during the year ended December 31, 2023. As a result of these and other factors, we do not believe that our historical results of operations discussed and analyzed below are comparable or necessarily indicative of our future results of operations or cash flows.

The following discussion and analysis of the results of our operations and financial condition for the year ended December 31, 2023 compared to the year ended December 31, 2022 should be read in conjunction with the accompanying consolidated financial statements included in Item 8. The discussion and analysis of the results of our operations and financial condition for the year ended December 31, 2022 compared to the year ended December 31, 2021, can be found in Part II, "Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations" of our Annual Report on Form 10-K for the year ended December 31, 2022, which was filed with the SEC on February 27, 2023.

Certain figures, such as interest rates and other percentages, included in this section have been rounded for ease of presentation. Percentage figures included in this section have not in all cases been calculated on the basis of such rounded figures but on the basis of such amounts prior to rounding. For this reason, percentage amounts in this section may vary slightly from those obtained by performing the same calculations using the figures in our consolidated financial statements or in the associated text. Certain other amounts that appear in this section may similarly not sum due to rounding.

Year Ended December 31, 2023 compared to the Year Ended December 31, 2022

Overview

The following table illustrates the changes in rental revenue, other property-related revenue, management fees and other revenue, property operating expenses, and other expenses for the year ended December 31, 2023 compared to the year ended December 31, 2022 (dollars in thousands):

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	Year Ended December 31,
	2023		2022		Change

Rental revenue	$	793,966	$	748,814	$	45,152
Other property-related revenue	29,686		25,131		4,555
Management fees and other revenue	34,411		27,624		6,787
Total revenue	858,063		801,569		56,494
Property operating expenses	228,986		211,025		17,961
General and administrative expenses	59,281		59,311		(30)
Depreciation and amortization	221,993		233,158		(11,165)
Other	11,108		8,537		2,571
Total operating expenses	521,368		512,031		9,337
Other (expense) income
Interest expense	(166,147)		(110,599)		(55,548)
Loss on early extinguishment of debt	(758)		—		(758)
Equity in earnings of unconsolidated real estate ventures	7,553		7,745		(192)
Acquisition costs	(1,659)		(2,745)		1,086
Non-operating expense	(1,016)		(951)		(65)
Gain on sale of self storage properties	63,910		5,466		58,444
Other expense, net	(98,117)		(101,084)		2,967
Income before income taxes	238,578		188,454		50,124
Income tax expense	(1,590)		(4,689)		3,099
Net income	236,988		183,765		53,223
Net income attributable to noncontrolling interests	(80,319)		(80,028)		(291)
Net income attributable to National Storage Affiliates Trust	156,669		103,737		52,932
Distributions to preferred shareholders	(19,019)		(13,425)		(5,594)
Net income attributable to common shareholders	$	137,650	$	90,312	$	47,338

Total Revenue

Our total revenue, including management fees and other revenue, increased by $56.5 million, or 7.0%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022. This increase was primarily attributable to incremental revenue from 20 self storage properties acquired during the year ended December 31, 2023 and from 45 self storage properties acquired during 2022, that were owned during the entire year ended December 31, 2023 and increases in management fees and other revenue from our unconsolidated real estate ventures. Total revenue increased despite a decrease in total portfolio average occupancy from 91.9% for the year ended December 31, 2022 to 88.0% for the year ended December 31, 2023. Average occupancy is calculated based on the average of the month-end occupancy immediately preceding the period presented and the month-end occupancies included in the respective period presented.

Rental Revenue

Rental revenue increased by $45.2 million, or 6.0%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022. The increase in rental revenue was primarily attributable to incremental rental revenue of $11.7 million from 20 self storage properties acquired during 2023, and $18.9 million from 45 self storage properties acquired during 2022, that were owned during the entire year ended December 31, 2023. Annualized total portfolio rental revenues (including fees and net of any discounts and uncollectible customer amounts) divided by average occupied square feet ("average annualized rental revenue per occupied square foot") increased from $14.83, for the year ended December 31, 2022 to $15.24, or 2.8%, for the year ended December 31, 2023, driven primarily by increased contractual lease rates for in-place tenants.

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Other Property-Related Revenue

Other property-related revenue represents ancillary income from our self storage properties, such as tenant insurance-related access fees and sales of storage supplies. Other property-related revenue increased by $4.6 million, or 18.1%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022. This increase primarily resulted from an increase in tenant insurance revenue of $4.4 million.

Management Fees and Other Revenue

Management fees and other revenue, which includes revenue related to managing and operating the unconsolidated real estate ventures and other revenue from our tenant insurance programs, increased $6.8 million, or 24.6%, for the year ended December 31, 2023, compared to the year ended December 31, 2022. This increase was primarily attributable to changes in our tenant insurance programs.

Property Operating Expenses

Property operating expenses increased by $18.0 million, or 8.5%, for the year ended December 31, 2023, compared to the year ended December 31, 2022. The increase in property operating expenses was primarily attributable to incremental property operating expenses of $3.8 million from 20 self storage properties acquired during 2023, and $6.6 million from 45 self storage properties acquired during 2022, that were owned during the entire year ended December 31, 2023.

General and Administrative Expenses

General and administrative expenses remained relatively consistent for the year ended December 31, 2023, compared to the year ended December 31, 2022. This result was primarily attributable to decreases in supervisory and administrative fees charged by our PROs resulting from the decrease in the number of properties managed by our PROs, partially offset by an increase in equity based compensation expense.

Depreciation and Amortization

Depreciation and amortization decreased $11.2 million, or 4.8%, for the year ended December 31, 2023, compared to the year ended December 31, 2022. This decrease was primarily attributable to amortization expense for customer in-place leases decreasing from $34.4 million for the year ended December 31, 2022 to $8.3 million for the year ended December 31, 2023, and partially offset by the incremental depreciation expense related to the 20 self storage properties acquired during 2023 and 45 self storage properties acquired during 2022, that were owned during the entire year ended December 31, 2023.

Other

Other expenses increased $2.6 million, or 30.1%, for the year ended December 31, 2023, compared to the year ended December 31, 2022. This increase was primarily attributable to increases in administrative costs relating to our tenant insurance programs and our reserves for casualty-related expenses and losses, each resulting from continued growth in our portfolio.

Interest Expense

Interest expense increased $55.5 million, or 50.2%, for the year ended December 31, 2023, compared to the year ended December 31, 2022. The increase in interest expense was primarily attributable to an increase in the effective interest rate under our revolving line of credit from 5.69%, as of December 31, 2022, to 6.71% as of December 31, 2023, and, to a lesser extent, an increase in overall average borrowings outstanding.

Loss on Early Extinguishment of Debt

Loss on early extinguishment of debt was $0.8 million for the year ended December 31, 2023. During the year ended December 31, 2023, in connection with an amendment to our credit facility, two of the lenders that were included in the syndicated group of lenders prior to the amendment are no longer participating lenders following the amendment, which constitutes an extinguishment of debt for accounting purposes. Additionally, in connection with the amendment we retired two term loans prior to their contractual maturity. Loss on early extinguishment of debt includes costs incurred related to these extinguishments, and the write off of $0.4 million of unamortized debt issuance costs related to the retired term loans or attributed to the entities no longer included in the lender syndicate.

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Equity In Earnings Of Unconsolidated Real Estate Ventures

Equity in earnings of unconsolidated real estate ventures represents our share of earnings and losses incurred through our 25% ownership interests in the 2018 Joint Venture and the 2016 Joint Venture. During the year ended December 31, 2023, we recorded $7.6 million of equity in earnings from our unconsolidated real estate ventures compared to $7.7 million for the year ended December 31, 2022.

Gain on Sale of Self Storage Properties

Gain on sale of self storage properties increased $58.4 million, for the year ended December 31, 2023, compared to the year ended December 31, 2022. The increase in gain on sale of self storage properties was primarily attributable to the sale of 32 self storage properties for net proceeds of $261.8 million.

Net Income Attributable to Noncontrolling Interests

As discussed in Note 2 to the consolidated financial statements in Item 8, we allocate U.S. generally accepted accounting principles ("GAAP") income (loss) utilizing the HLBV method, in which we allocate income or loss based on the change in each unitholders' claim on the net assets of our operating partnership at period end after adjusting for any distributions or contributions made during such period.

Due to the stated liquidation priorities and because the HLBV method incorporates non-cash items such as depreciation expense, in any given period, income or loss may be allocated disproportionately to noncontrolling interests. Net income attributable to noncontrolling interests was $80.3 million for the year ended December 31, 2023, compared to $80.0 million for the year ended December 31, 2022.

Critical Accounting Policies and Use of Estimates

Our financial statements have been prepared on the accrual basis of accounting in accordance with GAAP. The preparation of these financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, we evaluate our estimates and assumptions, including those that impact our most critical accounting policies. We base our estimates and assumptions on historical experience and on various other factors that we believe are reasonable under the circumstances. Our critical accounting estimates are defined as accounting estimates or assumptions made in accordance with GAAP, which involve a significant level of estimation, uncertainty or subjectivity and have had or are reasonably likely to have a material impact on our financial condition or results of operations. Actual results may differ from these estimates. We believe the following are our most critical accounting policies.

Principles of Consolidation and Presentation of Noncontrolling Interests

Our consolidated financial statements include the accounts of our operating partnership and its controlled subsidiaries. All significant intercompany balances and transactions have been eliminated in the consolidation of entities.

The limited partner ownership interests in our operating partnership that are held by owners other than us are referred to as noncontrolling interests. Noncontrolling interests also include ownership interests in DownREIT partnerships held by entities other than our operating partnership. Noncontrolling interests in a subsidiary are generally reported as a separate component of equity in our consolidated balance sheets. In our consolidated statements of operations, the revenues, expenses and net income or loss related to noncontrolling interests in our operating partnership are included in the consolidated amounts, with net income or loss attributable to the noncontrolling interests deducted separately to arrive at the net income or loss solely attributable to us.

When we obtain an economic interest in an entity, we evaluate the entity to determine if the entity is deemed a variable interest entity ("VIE"), and if we are deemed to be the primary beneficiary, in accordance with authoritative guidance issued on the consolidation of VIEs. When an entity is not deemed to be a VIE, we consider the provisions of additional guidance to determine whether the general partner controls a limited partnership or similar entity when the limited partners have certain rights. We consolidate all entities that are VIEs and of which the Company is deemed to be the primary beneficiary.

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Self Storage Properties and Customer In-Place Leases

Self storage properties are carried at historical cost less accumulated depreciation and any impairment losses. When self storage properties are acquired, the purchase price is allocated to the tangible and intangible assets acquired and liabilities assumed based on estimated fair values. The purchase price is allocated to the individual properties based on the fair value determined using an income approach or a cash flow analysis using appropriate risk adjusted capitalization rates, which take into account the relative size, age, and location of the individual properties along with current and projected occupancy and relative rental rates or appraised values, if available. Tangible assets are allocated to land, buildings and related improvements, and furniture and equipment.

In allocating the purchase price for a self storage property acquisition, we determine whether the acquisition includes intangible assets. We allocate a portion of the purchase price to an intangible asset attributed to the value of customer in-place leases. Because the majority of tenant leases are on a month-to-month basis, this intangible asset represents the estimated value of the leases in effect on the acquisition date. This intangible asset is amortized to expense using the straight-line method over 12 months, the estimated average remaining rental period for the leases.

Non-GAAP Financial Measures

FFO and Core FFO

Funds from operations, or FFO, is a widely used performance measure for real estate companies and is provided here as a supplemental measure of our operating performance. The December 2018 Nareit Funds From Operations White Paper - 2018 Restatement, which we refer to as the White Paper, defines FFO as net income (as determined under GAAP), excluding: real estate depreciation and amortization, gains and losses from the sale of certain real estate assets, gains and losses from change in control, mark-to-market changes in value recognized on equity securities, impairment write-downs of certain real estate assets and impairment of investments in entities when it is directly attributable to decreases in the value of depreciable real estate held by the entity and after items to record unconsolidated partnerships and joint ventures on the same basis. Distributions declared on subordinated performance units and DownREIT subordinated performance units represent our allocation of FFO to noncontrolling interests held by subordinated performance unitholders and DownREIT subordinated performance unitholders. For purposes of calculating FFO attributable to common shareholders, OP unitholders, and LTIP unitholders, we exclude distributions declared on subordinated performance units, DownREIT subordinated performance units, preferred shares and preferred units. We define Core FFO as FFO, as further adjusted to eliminate the impact of certain items that we do not consider indicative of our core operating performance. These further adjustments consist of acquisition costs, gains on debt forgiveness, gains (losses) on early extinguishment of debt, casualty-related expenses, losses, and related recoveries and adjustments for unconsolidated partnerships and joint ventures.

Management uses FFO and Core FFO as key performance indicators in evaluating the operations of our properties. Given the nature of our business as a real estate owner and operator, we consider FFO and Core FFO as key supplemental measures of our operating performance that are not specifically defined by GAAP. We believe that FFO and Core FFO are useful to management and investors as a starting point in measuring our operational performance because FFO and Core FFO exclude various items included in net income (loss) that do not relate to or are not indicative of our operating performance such as gains (or losses) from sales of self storage properties and depreciation, which can make periodic and peer analyses of operating performance more difficult. Our computation of FFO and Core FFO may not be comparable to FFO reported by other REITs or real estate companies.

FFO and Core FFO should be considered in addition to, but not as a substitute for, other measures of financial performance reported in accordance with GAAP, such as total revenues, operating income and net income (loss). FFO and Core FFO do not represent cash generated from operating activities determined in accordance with GAAP and are not a measure of liquidity or an indicator of our ability to make cash distributions. We believe that to further understand our performance, FFO and Core FFO should be compared with our reported net income (loss) and considered in addition to cash flows computed in accordance with GAAP, as presented in our consolidated financial statements.

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The following table presents a reconciliation of net income to FFO and Core FFO for the periods presented (in thousands, except per share and unit amounts):


	Year Ended December 31,
	2023		2022		2021
Net income	$	236,988	$	183,765	$	146,935
Add (subtract):
Real estate depreciation and amortization	220,737		231,870		156,930
Company's share of unconsolidated real estate venture real estate depreciation and amortization	17,083		17,072		15,408
Gain on sale of self storage properties	(63,910)		(5,466)		—


Distributions to preferred shareholders and unitholders	(20,330)		(14,510)		(14,070)
FFO attributable to subordinated performance unitholders(1)	(49,040)		(58,838)		(49,810)
FFO attributable to common shareholders, OP unitholders, and LTIP unitholders	341,528		353,893		255,393
Add:
Acquisition costs	1,659		2,745		1,941
Casualty-related (recoveries) expenses(2)	(522)		6,388		—
Loss on early extinguishment of debt	758		—		—
Core FFO attributable to common shareholders, OP unitholders, and LTIP unitholders	$	343,423	$	363,026	$	257,334

Weighted average shares and units outstanding - FFO and Core FFO:(3)
Weighted average shares outstanding - basic	86,846		91,239		81,195
Weighted average restricted common shares outstanding	25		27		33
Weighted average effect of outstanding forward offering agreement(4)	—		—		100
Weighted average OP units outstanding	38,302		35,421		30,127
Weighted average DownREIT OP unit equivalents outstanding	2,120		1,925		1,925
Weighted average LTIP units outstanding	553		514		542
Total weighted average shares and units outstanding - FFO and Core FFO	127,846		129,126		113,922

FFO per share and unit	$	2.67	$	2.74	$	2.24
Core FFO per share and unit	$	2.69	$	2.81	$	2.26

(1) Amounts represent distributions declared for subordinated performance unitholders and DownREIT subordinated performance unitholders for the periods presented.

(2) Casualty-related recoveries in 2023 relate to casualty-related expenses incurred in 2022 and are recorded in the line item "Other" within operating expenses in our consolidated statement of operations.

(3) NSA combines OP units and DownREIT OP units with common shares because, after the applicable lock-out periods, OP units in the Company's operating partnership are redeemable for cash or, at NSA's option, exchangeable for common shares on a one-for-one basis and DownREIT OP units are also redeemable for cash or, at NSA's option, exchangeable for OP units in our operating partnership on a one-for-one basis, subject to certain adjustments in each case. Subordinated performance units, DownREIT subordinated performance units, and LTIP units may also, under certain circumstances, be convertible into or exchangeable for common shares (or other units that are convertible into or exchangeable for common shares). See footnote(1) to the following table for additional discussion of subordinated performance units, DownREIT subordinated performance units, and LTIP units in the calculation of FFO and Core FFO per share and unit.

(4) Represents the dilutive effect of the forward offering from the application of the treasury stock method.

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The following table presents a reconciliation of earnings per share - diluted to FFO and Core FFO per share and unit for the periods presented:


	Year Ended December 31,
	2023		2022		2021
Earnings per share - diluted	$	1.48	$	0.99	$	0.98
Impact of the difference in weighted average number of shares(1)	0.23		(0.28)		0.18
Impact of GAAP accounting for noncontrolling interests, two-class method and treasury stock method(2)	—		0.62		—
Add real estate depreciation and amortization	1.73		1.79		1.38
Add Company's share unconsolidated venture real estate depreciation and amortization	0.13		0.13		0.14
Subtract gain on sale of self storage properties	(0.52)		(0.05)		—

FFO attributable to subordinated performance unitholders	(0.38)		(0.46)		(0.44)
FFO per share and unit	2.67		2.74		2.24
Add acquisition costs and Company's share of unconsolidated real estate venture acquisition costs	0.01		0.02		0.02
Add casualty-related expenses	—		0.05		—
Add loss on early extinguishment of debt	0.01		—		—
Core FFO per share and unit	$	2.69	$	2.81	$	2.26

(1) Adjustment accounts for the difference between the weighted average number of shares used to calculate diluted earnings per share and the weighted average number of shares used to calculate FFO and Core FFO per share and unit. Diluted earnings per share is calculated using the two-class method for the company's restricted common shares, the treasury stock method for certain unvested LTIP units, and includes the assumption of a hypothetical conversion of subordinated performance units and DownREIT subordinated performance units into OP units, even though such units may only be convertible into OP units (i) after a lock-out period and (ii) upon certain events or conditions. For additional information about the conversion of subordinated performance units, DownREIT subordinated performance units and LTIP units into OP units, see Note 10 to the consolidated financial statements in Item 8. The computation of weighted average shares and units for FFO and Core FFO per share and unit includes all restricted common shares and LTIP units that participate in distributions and excludes all subordinated performance units and DownREIT subordinated performance units because their effect has been accounted for through the allocation of FFO to the related unitholders based on distributions declared.
(2) Represents the effect of adjusting the numerator to consolidated net income (loss) prior to GAAP allocations for noncontrolling interests, after deducting preferred share and unit distributions, and before the application of the two-class method and treasury stock method, as described in footnote(1).

Net Operating Income

Net operating income, or NOI, represents rental revenue plus other property-related revenue less property operating expenses. NOI is not a measure of performance calculated in accordance with GAAP.

We believe NOI is useful to investors in evaluating our operating performance because:

•NOI is one of the primary measures used by our management and our PROs to evaluate the economic productivity of our properties, including our ability to lease our properties, increase pricing and occupancy and control our property operating expenses;

•NOI is widely used in the real estate industry and the self storage industry to measure the performance and value of real estate assets without regard to various items included in net income that do not relate to or are not indicative of operating performance, such as depreciation and amortization, which can vary depending upon accounting methods, the book value of assets, and the impact of our capital structure; and

•We believe NOI helps our investors to meaningfully compare the results of our operating performance from period to period by removing the impact of our capital structure (primarily interest expense on our outstanding indebtedness) and depreciation of the cost basis of our assets from our operating results.

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There are material limitations to using a non-GAAP measure such as NOI, including the difficulty associated with comparing results among more than one company and the inability to analyze certain significant items, including depreciation and interest expense, that directly affect our net income (loss). We compensate for these limitations by considering the economic effect of the excluded expense items independently as well as in connection with our analysis of net income (loss). NOI should be considered in addition to, but not as a substitute for, other measures of financial performance reported in accordance with GAAP, such as total revenues and net income (loss).

As of December 31, 2023, our same store portfolio consisted of 724 self storage properties. Our same store portfolio is defined as those properties owned and operated since the first day of the earliest year presented, excluding any properties sold, expected to be sold or subject to significant changes such as expansions or casualty events which cause the portfolio's year-over-year operating results to no longer be comparable. The following table illustrates the changes in rental revenue, other property-related revenue, and property operating expenses, for the year ended December 31, 2023 compared to the year ended December 31, 2022 (dollars in thousands):


	Year Ended December 31,
	2023		2022		Change
Rental revenue
Same store portfolio	$	646,893	$	633,708	$	13,185
Non-same store portfolio	147,073		115,106		31,967
Total rental revenue	793,966		748,814		45,152
Other property-related revenue
Same store portfolio	23,634		20,821		2,813
Non-same store portfolio	6,052		4,310		1,742
Total other property-related revenue	29,686		25,131		4,555
Property operating expenses
Same store portfolio	178,006		169,987		8,019
Non-same store portfolio	50,980		41,338		9,642
Prior period comparability adjustment	—		(300)		300
Total property operating expenses	228,986		211,025		17,961
Net operating income
Same store portfolio	492,521		484,542		7,979
Non-same store portfolio	102,145		78,378		23,767
Total net operating income	$	594,666	$	562,920	$	31,746

Rental Revenue

Same store portfolio rental revenues increased $13.2 million, or 2.1%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022. Average annualized same store rental revenue per occupied square foot increased from $14.89 to $15.80, or 6.1%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022, driven primarily by increased contractual lease rates for in-place tenants. This increase in same store portfolio rental revenue was partially offset by a decrease in average occupancy from 93.1% for the year ended December 31, 2022 to 89.1% for the year ended December 31, 2023.

Other Property-Related Revenue

Same store portfolio other property-related revenue increased $2.8 million, or 13.5%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022. This increase primarily resulted from an increase in tenant insurance revenue.

Table of Contents

Property Operating Expenses

Same store portfolio property operating expenses increased $8.0 million, or 4.7%, for the year ended December 31, 2023, as compared to the year ended December 31, 2022. The increase in same store property operating expenses was a result of increases in marketing, insurance and property tax expense partially offset by a decrease in personnel costs during the year ended December 31, 2023.

The following table presents a reconciliation of net income to NOI for the periods presented (dollars in thousands):


	Year Ended December 31,
	2023		2022		2021
Net income	$	236,988	$	183,765	$	146,935
(Subtract) add:
Management fees and other revenue	(34,411)