UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

National Storage Affiliates Trust

(720) 630-2600
(Registrant's telephone number, including area code)

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. ☐

On January 29, 2018, pursuant to a full exercise by NSA OP, LP (the "Operating Partnership") of its remaining expansion option and a partial exercise of its Additional Expansion Option (defined below) under its amended and restated credit agreement dated as of May 6, 2016 (as amended, the "Credit Agreement"), the Operating Partnership, as borrower, certain of its subsidiaries that are party to the Credit Agreement, as subsidiary guarantors, and National Storage Affiliates Trust (the "Company"), as parent guarantor, entered into a third increase agreement and amendment (the "Increase Agreement") with KeyBank National Association, as Administrative Agent (the "Administrative Agent"), and the lenders party thereto, as the increase lenders, to provide a new tranche D term loan facility ("Term Loan D") in an aggregate outstanding principal amount of $125.0 million, which increases the total borrowing capacity under the credit facility to $1.02 billion, consisting of four components: (i) a $400.0 million revolving line of credit, (ii) a tranche A term loan facility, which provides for a total borrowing commitment of up $235.0 million, (iii) a tranche B term loan facility, which provides for a total borrowing commitment of up to $155.0 million, (iv) a tranche C term loan facility, which provides for a total borrowing commitment of up to $105.0 million, and (v) Term Loan D, which provides for a total borrowing commitment of up to $125.0 million. The Operating Partnership renewed the expansion option under the credit facility to permit an additional $300 million of revolving commitments and/or term loans (the "Additional Expansion Option"), which was partially exercised in the amount of $20 million in connection with Term Loan D. If exercised in full, the Additional Expansion Option would provide for a total borrowing capacity under the credit facility of $1.3 billion.

On November 15, 2017, the Operating Partnership issued 59,375 Class A common units of limited partner interest in the Operating Partnership ("OP units") and 8,218 Class B common units of limited partner interest in the Operating Partnership ("subordinated performance units"), as partial consideration for the acquisition of one self storage property from Newberg Storage LLC, an affiliate of Kevin Howard Real Estate Inc., d/b/a Northwest Self Storage ("Northwest"), one of the Company's existing participating regional operators ("PROs") and an affiliate of Kevin Howard, a trustee of the Company.

On December 14, 2017, the Operating Partnership issued 181,981 OP units and 121,320 subordinated performance units, including 60,660 subordinated performance units to Howard Family Limited Partnership I ("HFLP"), an affiliate of Kevin Howard, a trustee of the Company, as partial consideration for the acquisition of one self storage property from HFLP and unrelated third parties.

On February 1, 2018, January 11, 2018 and January 4, 2018, the Operating Partnership issued, in the aggregate, 316,103 6.000% Series A-1 cumulative redeemable preferred units of limited partnership interest in the Operating Partnership ("Series A-1 Preferred Units") and 464,056 OP units as consideration for the acquisition of a portfolio of fifteen self storage properties from an unrelated third party.

Following a specified lock up period after the respective dates of issuance set forth above, the OP units and Series A-1 Preferred Units issued by the Operating Partnership may be redeemed from time to time by holders for a cash amount per OP unit or Series A-1 Preferred Unit, respectively, equal to the market value of an equivalent number of common shares of beneficial interest of the Company ("Common Shares") or 6.000% Series A cumulative redeemable preferred shares of beneficial interest of the Company (Series A Preferred Shares"), respectively. 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 and one Series A Preferred Share in exchange for each Series A-1 Preferred 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.

As of February 2, 2018, other than those OP units held by the Company, after reflecting the transactions described herein, 29,783,462 OP units of the Operating Partnership were outstanding (including 779,506 outstanding LTIP units and 1,834,786 outstanding OP units ("DownREIT OP units") in certain consolidated subsidiaries of the Operating Partnership, which are convertible into, or exchangeable for, OP units on a one-for-basis, subject to certain conditions).