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    Our trustee nominees represent a mix of independence, age, race, gender, tenure, skills and experience:

•FOR the election of the eleven trustee nominees named in this Proxy Statement as trustees;

•FOR the ratification of the appointment of KPMG LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2021; and

•FOR the advisory approval of the compensation of the Named Executive Officers as described in this Proxy Statement.

We seek highly qualified trustee candidates from diverse business, professional and educational backgrounds who combine a broad spectrum of experience and expertise with a reputation for the highest personal and professional ethics, integrity and values. The CNCG Committee considers diversity of gender, race, age, experience and skills as important factors in choosing the most qualified candidates. We believe that, as a group, the nominees bring a broad range of perspectives that contribute to the effectiveness of our board of trustees as a whole. The procedures and considerations of the CNCG Committee in recommending qualified trustee candidates are described below under "Corporate Governance–Identification of Trustee Candidates" in this Proxy Statement. The CNCG Committee and our board of trustees concluded that each of our trustee nominees should be nominated for election based on the qualifications and experience described in the biographical information below under "–Information Regarding Nominees for Election as Trustees."

It is intended that the Common Shares represented by properly submitted proxies will be voted by the persons named therein as proxy holders FOR the election of Messrs. Nordhagen, Chapman, Hylbert, Meisinger, Osgood, Palazzo, Van Mourick, Warren and Wu and Mss. Fischer and Steinfort as trustees, unless otherwise instructed. If the candidacy of any trustee nominee should, for any reason, be withdrawn prior to the Annual Meeting, the proxies will be voted by the proxy holders in favor of such substituted candidates (if any) as shall be nominated by our board of trustees. Our board of trustees has no reason to believe that, if elected, any of the nominees will be unable or unwilling to serve as a trustee.

Our board of trustees recommends a vote FOR the election of Messrs. Nordhagen, Chapman, Hylbert, Meisinger, Osgood, Palazzo, Van Mourick, Warren and Wu and Mss. Fischer and Steinfort as trustees.

We have not received notice of any additional candidates to be nominated for election as trustees at the Annual Meeting and the deadline for notice of additional candidates has passed. Consequently, the election of trustees will be an uncontested election and the provisions of our Second Amended and Restated Bylaws (the "Bylaws") providing for majority voting in uncontested elections will apply. See "Corporate Governance–Majority Vote and Trustee Resignation Policy" below. Under majority voting, to be elected as a trustee, a nominee must receive votes "FOR" his or her election constituting a majority of the total votes cast for and against such nominee at the Annual Meeting at which a quorum is present. If a nominee who currently is serving as a trustee does not receive sufficient "FOR" votes to be re-elected, Maryland law provides that the trustee would continue to serve on our board of trustees as a "holdover" trustee. Under our Bylaws and corporate governance guidelines (the "Guidelines"), he or she must submit his or her resignation to our board of trustees. Our CNCG Committee will consider such tendered resignation and recommend to our board of trustees whether to accept it. Our board of trustees will decide whether to accept any such resignation within 90 days after certification of the election results and will publicly disclose its decision. If the resignation is not accepted, the trustee will continue to serve until the trustee's successor is duly elected and qualifies or until the trustee's earlier death, resignation, retirement or removal. If a trustee’s offer to resign is accepted by our board of trustees, or if a nominee for trustee is not elected and the nominee is not an incumbent trustee, then our board of trustees, in its sole discretion, may fill any resulting vacancy pursuant to the Bylaws. Proxies solicited by our board of trustees will be voted FOR Messrs. Nordhagen, Chapman, Hylbert, Meisinger, Osgood, Palazzo, Van Mourick, Warren and Wu and Mss. Fischer and Steinfort, unless otherwise

The table below summarizes the compensation received by our independent trustees during 2020.

Each independent trustee is subject to our minimum equity ownership guidelines. See "Compensation Discussion and Analysis–Minimum Equity Ownership Guidelines."

Our board of trustees has adopted Corporate Governance Guidelines that address significant issues of corporate governance and set forth procedures by which our board of trustees carries out its responsibilities, including the trustee resignation policy as described under "–Majority Vote and Trustee Resignation Policy" below. In addition, among the areas addressed by the Guidelines are the composition of our board of trustees, its functions and responsibilities, its standing committees, its PRO advisory committee, trustee qualification standards, access to management and independent advisors, trustee compensation, management succession, trustee orientation and continuing education, and the annual performance evaluation and review of our board of trustees and committees. The Guidelines are available for viewing on our website at www.nationalstorageaffiliates.com. We will also provide the Guidelines, free of charge, to shareholders who request it. Requests should be directed to our corporate secretary at National Storage Affiliates Trust, 8400 East Prentice Avenue, 9th Floor, Greenwood Village, CO 80111.

Our board of trustees has approved a process to enable communications with the independent members of the board of trustees, including our lead independent trustee, or the chair of any of the committees of the board of trustees. Communications by email should be sent to NSABoard@nsareit.net. Communications by regular mail should be sent to the attention of Tamara D. Fischer, our president, chief executive officer and trustee, at National Storage Affiliates Trust, 8400 East Prentice Avenue, 9th Floor, Greenwood Village, CO 80111. Each communication received will be reviewed to determine whether the communication requires immediate action. All appropriate communications received, or a summary of such communications, will be sent to the appropriate member(s) of our board of trustees. However, we reserve the right to disregard any communication we determine is unduly hostile, threatening, illegal, does not reasonably relate to us or our business, or is similarly inappropriate. Our corporate secretary, or her delegate, has the authority to disregard any inappropriate communications or to take other appropriate actions with respect to any such inappropriate communications. In addition, any of our shareholders and any other person may make a good faith report to the Audit Committee regarding any questionable or unethical accounting or auditing matters via regular mail addressed to the Audit Committee, National Storage Affiliates Trust, 8400 East Prentice Avenue, 9th Floor, Greenwood Village, CO 80111. We also encourage members of our board of trustees to be available to speak to institutional shareholders outside of formal meeting settings.

Our board of trustees values the input and insights of our shareholders and believes that effective shareholder engagement strengthens the board's role as an informed and engaged fiduciary. We are committed to serving our shareholders’ interests and recognize that communicating with shareholders on a regular basis is a critical component of our corporate governance program. As part of this commitment, management actively engages with our shareholders in order to fully understand their viewpoints concerning our Company, to gather feedback on what we can do better and to help our shareholders understand our performance and strategy. In addition to answering questions from shareholders on our quarterly earnings calls, our management regularly engages with shareholders by participating in industry conferences, through in-person and virtual meetings with our shareholders and prospective investors, and by telephone with many shareholders at other times throughout the year to solicit input and answer questions on a variety of topics. During 2020, we held approximately 145 of such meetings with current and prospective investors to discuss various key corporate matters, including our differentiated growth strategy, financing strategy, risk management practices, and strong corporate governance practices. Interested parties, including shareholders, may communicate their concerns directly to the independent members of our board of trustees, including our lead independent trustee, or the chair of any of the committees of the board of trustees as described above under "–Communications with the Board of Trustees," or to management.

•holders of a majority of the Company's Common Shares outstanding as of the Determination Date (as defined below); and

•holders of Common Shares and limited partners (other than the Company) of our operating partnership representing a majority of the number of Common Shares outstanding as of the Determination Date together with the number of additional Common Shares that would be issuable if:

◦all OP units outstanding as of the Determination Date were exchanged on a one-for-one basis, subject to adjustments as provided in the Third Amended and Restated Agreement of Limited Partnership of our operating partnership (as amended, the "Partnership Agreement"), for Common Shares, and

◦the OP units which would be outstanding if each series of subordinated performance units (or other similar class or series of OP units created from time to time) outstanding as of the Determination Date (whether or not then convertible) were converted into OP units using the conversion ratio for each such class or series in effect as of the last day of the most recent fiscal year determined pursuant to the terms of the Partnership Agreement and as approved by the Company's board of trustees, were exchanged on a one-for-one basis, subject to adjustments as provided in the Partnership Agreement, for Common Shares.

Biographies for our executive officers as of December 31, 2020, other than Mr. Nordhagen and Ms. Fischer, are set forth below. Biographical information for Mr. Nordhagen and Ms. Fischer is set forth under "Proposal 1: Election of Trustees–Information Regarding the Nominees for Election as Trustees." All of our executive officers are Named Executive Officers.

•Mr. Nordhagen became our executive chairman;

•Ms. Fischer became our president and chief executive officer; and

•Mr. Togashi became our executive vice president, chief financial officer, chief accounting officer and treasurer.

Named Executive Officers to achieve our business objectives and aligning their interests with those of our shareholders. In 2020, more than 70% of our Named Executive Officers' target pay was at risk.

Our same store portfolio is defined in our annual report on Form 10-K filed with the SEC on February 26, 2021. Core FFO and NOI are defined and reconciled to their most directly comparable GAAP measure in Appendix A to this Proxy Statement.

    Our total TSR performance was approximately 50% and 160% over the three-year and five-year periods ended December 31, 2020, respectively. As a result, for the three-year period ended December 31, 2020, we outperformed three of our public company self storage REIT peers and ranked 23rd out of 138 REITs in the MSCI US REIT Index, and for the five-year period ended December 31, 2020, we outperformed all of our public company self storage REIT peers and ranked 12th out of 138 REITs in the MSCI US REIT Index.

        Source: S&P Global Market Intelligence

    CNCG Committee

    Compensation Consultant

Mr. Nordhagen, our executive chairman, and Ms. Fischer, our president and chief executive officer, generally attend CNCG Committee meetings and provide information as to the individual performance of the Named Executive Officers and other key employees. Prior to January 1, 2020, Mr. Nordhagen, as our chief executive officer, made annual recommendations to our CNCG Committee of appropriate compensation levels for our other Named Executive Officers, as well as for other key employees. After January 1, 2020, Ms. Fischer makes the annual recommendations to our CNCG Committee with respect to our other Named Executive Officers (including Mr. Nordhagen) and other key employees. Nonetheless, all components of our Named Executive Officers' compensation are approved by our CNCG Committee in its sole discretion and our chief executive officer is not present during our CNCG Committee’s determination with respect to her own compensation.

Our CNCG Committee, in consultation with FPL, conducts compensation benchmarking analyses to ensure that our compensation programs for our Named Executive Officers and independent trustees are competitive with those of certain other publicly traded REITs (each, a "Benchmarking Analysis" and together, the "Benchmarking Analyses"). The Benchmarking Analyses include a comprehensive review of each component of the total compensation opportunities for our Named Executive Officers and independent trustees relative to market data for REITs with market capitalization and enterprise value similar to that of our Company. We refer to this group of REITs as our "peer group". The peer group used for the 2019 independent trustee Benchmarking Analysis and 2020 Named Executive Officer Benchmarking Analysis is listed below.

The market data for our Named Executive Officers was sourced from FPL’s proprietary database and the 2018, 2019 and 2020 Nareit Compensation Surveys conducted by FPL. For our independent trustees, the market data was sourced from the January 2019 National Association of Corporate Directors Director Compensation Report, the Top 100 Real Estate Compensation Analysis conducted by FPL in June 2019, and the public filings of the REITs included in the analysis. This information was considered by our CNCG Committee in approving increased annual base salaries for our Named Executive Officers in 2020 and 2021, as set forth below under "Elements of our Compensation Program–Base Salary." The independent trustee Benchmarking Analysis was considered by our CNCG Committee in approving our independent trustee compensation program for 2020 and 2021, as described above under "Compensation of Independent Trustees." Any changes approved are intended to better align each Named Executive Officer's and independent trustee's total compensation with the peer group.

    We strive to adopt policies and practices that we believe are in the best interests of our Company and our shareholders. See "Corporate Governance–Governance Highlights" and "Corporate Governance–Active Shareholder Outreach and Corporate Governance" for additional information.

KEY FEATURES OF OUR COMPENSATION PROGRAM

    Base Salary

    Annual Incentive Cash Bonus Payments

•the adjusted maximum payout for Same Store NOI growth was capped at the original target amount of the cash bonus opportunity;

•the adjusted target payout for Same Store NOI growth was reduced to 50% of the original target amount of the cash bonus opportunity;

•the adjusted threshold payout for Same Store NOI growth was reduced to zero; and

•the adjusted payout for any other level of performance between the threshold and maximum performance levels would be determined by linear interpolation.

    Long-Term Equity Incentive Compensation

•Encourage management to create shareholder value over the long-term;

•Promote management retention because full vesting of the awards generally requires continued employment for multiple years; and

•Encourage Company growth and the achievement of our business strategies that can take more than one year to execute when they are tied to specific performance criteria.

•in the case of a termination by us without "cause" or by the Named Executive Officer for "good reason", 100% of the unvested LTIP awards held by the Named Executive Officer will become fully vested and free of restrictions.

•in the case of a termination due to death or disability, the following vesting terms ("Death or Disability Vesting Terms") apply with respect to outstanding unvested awards held by the Named Executive Officer:

◦with respect to outstanding unvested time-based share awards, a prorated portion (based on the number of days of employment since the immediately preceding January 1st until the date of death or disability, as applicable, over 365) of such awards that would have vested on the next vesting date applicable to such awards will become vested and free of restrictions and any remaining portion of such awards will be forfeited; and

◦with respect to outstanding unvested performance-based share awards, such awards shall vest as set forth in the applicable award agreements underlying such awards, as follows: a prorated portion of any unvested performance-based LTIP unit awards will vest based on the applicable number of days worked in each applicable three-year performance period over 1,095 as set forth in each LTIP unit award agreement, except in the event that a termination of service as described above follows a change of control which occurs more than eighteen (18) months after the beginning of the performance period, in which case all outstanding performance-based LTIP units for such performance period will vest without being subject to proration in accordance with the calculation set forth in the LTIP unit award agreements. For more information, see "Employment Agreements" herein.

    Restricted Shares

    Dividend Equivalents

    LTIP Units

    Other Equity-Based Awards

AMENDMENTS AND TERMINATION

•other than through adjustment as provided in our Equity Incentive Plan, increase the total number of Common Shares reserved for issuance under our Equity Incentive Plan;

•materially expand the class of trustees, officers, employees, consultants and advisors eligible to participate in our Equity Incentive Plan;

•reprice any share options under our Equity Incentive Plan; or

•otherwise require such approval.

•a specified minimum annual base salary, subject to increases at the discretion of our board of trustees or the CNCG Committee;

•eligibility for annual cash performance bonuses based on the satisfaction of performance goals established by our board of trustees or our CNCG Committee, which will be awarded at the discretion of our CNCG Committee;

•participation in our Equity Incentive Plan (including eligibility for regular, annual grants under the plan), as well as other incentive, savings and retirement plans applicable generally to Named Executive Officers; and

•medical and other group welfare plan coverage and fringe benefits provided to our Named Executive Officers.

•accrued but unpaid base salary, bonus and other benefits earned and accrued but unpaid prior to the date of termination;

•an amount equal to the sum of the Named Executive Officer's then-current annual base salary plus the greater of the annual average bonus over the prior two years (or such fewer years with respect to which the Named Executive Officer received an annual bonus) and the Named Executive Officer's target annual bonus for the year of termination, multiplied by the applicable multiple set forth below for each Named Executive Officer;

•health benefits for the Named Executive Officer and eligible family members for two years following the Named Executive Officer's termination of employment at the same level as in effect immediately preceding such termination, subject to reduction to the extent that the Named Executive Officer receives comparable benefits from a subsequent employer; and

•100% of the unvested shares or share-based awards held by the Named Executive Officer will become fully vested and/or exercisable.

•accrued but unpaid base salary, bonus and other benefits earned and accrued but unpaid prior to the date of termination;

•prorated annual bonus for the year in which the termination occurs;

•health benefits for the Named Executive Officer and/or eligible family members for two years following the Named Executive Officer's termination of employment at the same level as in effect immediately preceding the Named Executive Officer's death or disability; and

•for all outstanding unvested share awards held by the Named Executive Officer, the Death or Disability Terms shall apply. For information about the Death or Disability Terms, see "Compensation Discussion and Analysis–Elements of our Compensation Program–Long-Term Equity Incentive Compensation."

CLAWBACK POLICY

TAX IMPLICATIONS - DEDUCTIBILITY OF NAMED EXECUTIVE OFFICER COMPENSATION

•We included all of our employees in the analysis (other than Ms. Fischer), including full-time, part-time and seasonal employees, who were employed by us on December 31, 2020.

•We reviewed the 2020 total W-2 compensation for all of our employees, subject to certain adjustments as described below.

•Due to the increase in the number of our employees as a result of the SecurCare internalization, as well as the rate of turnover in store employee positions that is customary for the industry, we approximated W-2 wages for our employees who were employed by us for less than a full year by annualizing the compensation of those full-time and part-time employees. The annualized compensation of hourly employees was calculated based upon a 2,080 hour year for full-time employees and a 1,040 hour year for part-time employees.

•We did not make any other assumptions, adjustments or estimates with respect to total W-2 compensation and did not apply any cost of living adjustments.

The following table sets forth certain information with respect to each grant of a plan-based award made to a Named Executive Officer in the fiscal year ended December 31, 2020. The following table reflects (i) under estimated future payouts under non-equity incentive plan awards, the threshold, target, and maximum performance goals under our 2020 annual incentive cash bonus program, (ii) under estimated future payouts under equity incentive plan awards, the threshold, target and maximum amount of LTIP unit awards granted to a Named Executive Officer that can vest contingent upon the achievement of performance criteria over a three-year performance period pursuant to the performance-based component of our long-term equity incentive plan, (iii) under all other share awards, the time-based LTIP unit awards granted in 2020 pursuant to our long-term equity incentive plan, and (iv) the grant date fair value of such awards. For additional information, see "Compensation Discussion and Analysis–Elements of our Compensation Program" above.