National Storage Affiliates Trust (NSA) Business

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, 2025, we held ownership interests in and operated a geographically diversified portfolio of 1,063 self storage properties located in 37 states and Puerto Rico, comprising approximately 69.4 million rentable square feet, configured in approximately 548,000 storage units, excluding three properties classified as held for sale that were sold to a third party in January 2026. 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 chairperson of the board of trustees and 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, which we refer to as our former PRO structure. Although the PRO structure contributed significantly to our growth over the last decade, the internalization of the PRO structure, which occurred on July 1, 2024, was always a part of our long term vision. Over time, largely through our unconsolidated real estate ventures, retirement of PROs and the internalization of our PRO structure, we have developed a full service internally-staffed property management platform.

We believe that our national platform has significant potential for continued external and internal growth. We seek to further expand our national platform by continuing to pursue strategic acquisitions, as well as to opportunistically partner 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.

Our Property Management Platform

Through our property management platform, we direct, manage and control the day-to-day operations and affairs of our consolidated properties and our unconsolidated real estate ventures. As of December 31, 2025, our property management platform managed and controlled substantially all of our 801 consolidated properties and 262 of our unconsolidated real estate venture properties. The properties are primarily managed by us under the brands of iStorage, Move It, Northwest, RightSpace, SecurCare and Southern.

We earn certain customary fees for managing and operating the properties in the managed 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 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, 2025, we owned a geographically diversified portfolio of 801 self storage properties located in 33 states and Puerto Rico, comprising approximately 51.1 million rentable square feet, configured in approximately 403,000 storage units, excluding three properties classified as held for sale that were sold to a third party in January 2026. Of these properties, 289 were acquired by us from our former PROs, 511 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, 2025, we acquired four consolidated self storage properties and annexes to existing properties, all of which were acquired by us from unaffiliated third-party sellers. The following is a summary of our 2025 consolidated acquisition activity (dollars in thousands):

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During the year ended December 31, 2025, we sold to unaffiliated third parties 15 self storage properties consisting of approximately 1.0 million rentable square feet configured in approximately 7,000 storage units for approximately $96.9 million.

During the year ended December 31, 2024, we acquired seven consolidated self storage properties and annexes to existing properties, all of which were acquired by us from unaffiliated third-party sellers. The following is a summary of our 2024 consolidated acquisition activity (dollars in thousands):

During the year ended December 31, 2024, we sold to unaffiliated third parties 40 self storage properties consisting of approximately 2.6 million rentable square feet configured in approximately 19,000 storage units for approximately $273.1 million and we contributed to the 2024 Joint Venture (as defined in Note 5 to the consolidated financial statements in Item 8) 56 self storage properties consisting of approximately 3.2 million rentable square feet configured in approximately 24,000 storage units for approximately $343.7 million.

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

As of December 31, 2025, our 2024 Joint Venture, in which we have a 25% ownership interest, owned and operated 56 self storage properties containing approximately 3.2 million rentable square feet, configured in approximately 24,000 storage units and located across seven states.

2023 Joint Venture

As of December 31, 2025, 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, owned and operated 21 self storage properties containing approximately 1.4 million rentable square feet, configured in approximately 9,000 storage units and located across five states.

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2018 Joint Venture

As of December 31, 2025, 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 7.9 million rentable square feet, configured in approximately 65,000 storage units and located across 17 states.

2016 Joint Venture

As of December 31, 2025, our 2016 Joint Venture, in which we have a 25% ownership interest, owned and operated 81 properties containing approximately 5.7 million rentable square feet, configured in approximately 47,000 storage units and located across 13 states.

IRE Investment

As of December 31, 2025, we had entered into an agreement with an affiliate of Investment Real Estate Management, LLC (the "IRE Member") to form a new venture to acquire self storage properties (the "IRE Investment"), whereby we committed to provide 75% of the equity capital, up to a maximum of $105.0 million in cash in exchange for preferred equity, and the IRE Member committed to provide 25% of the equity capital, up to a maximum of $35.0 million in cash in exchange for common equity. An affiliate of the IRE Member will serve as the manager of the IRE Investment and will manage the day-to-day operations of the self storage properties. As of December 31, 2025 the IRE Investment did not own any self storage properties.

Our Long-Term Business and Growth Strategies

With our diversified national portfolio of self storage properties, 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:

High Quality Properties in Key Growth Markets.    We held ownership interests in and operated a geographically diversified portfolio of 1,063 self storage properties located in 37 states and Puerto Rico, comprising approximately 69.4 million rentable square feet, configured in approximately 548,000 storage units as of December 31, 2025. Over 70% of our consolidated portfolio is located in the top 100 MSAs, based on our 2025 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.    Our national platform allows us to capture cost savings through integration and centralization, thereby eliminating redundancies and utilizing economies of scale. 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, we have 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.

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 are positively impacting our business performance, and we believe that they will continue to be a driver of organic growth going forward.

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. We believe that our efficient national platform and centralized infrastructure will enable us to achieve optimal market rents and occupancy, reduce operating expenses and increase the sale by us of ancillary products and services, including tenant insurance, of which we receive a portion of the proceeds, truck rentals and packing supplies.

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Participate in Industry Consolidation Through Acquisitions.    The self storage industry is highly fragmented, with the majority of self storage properties in the United States owned by private companies and owners, representing a significant consolidation opportunity. We have established an extensive network of industry relationships and contacts in our respective markets. Through these regional and local connections, we are able to access acquisition opportunities, including some opportunities that are not publicly marketed or sold through auctions. We believe our industry networks and underwriting expertise provide us with a competitive advantage in identifying and selecting attractive acquisition opportunities, in many cases, before they are publicly marketed. We also believe our reputation as a reliable, well-capitalized buyer, along with our willingness to use OP units as transactional currency for 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 tax-deferred alternatives.

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 managed unconsolidated real estate ventures, which as of December 31, 2025 owned 262 properties, to present a potential acquisition opportunity. This 75% third-party share of gross real estate assets is approximately $2.1 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.

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.

Credit Facility.  As of December 31, 2025, our unsecured credit facility provided for total borrowings of $1.355 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 D term loan facility (the "Term Loan D") and (iii) a $130.0 million tranche E term loan facility (the "Term Loan E"). As of December 31, 2025, we had the entire amounts drawn on Term Loan D and Term Loan E and we had approximately $400.9 million of outstanding borrowings under the Revolver, and the capacity to borrow an additional $542.1 million under the Revolver while remaining in compliance with the credit facility's financial covenants. As of December 31, 2025, we had an expansion option under the credit facility, which, if exercised in full, would have provided for a total credit facility of $1.900 billion.

Term Loan Facilities, Senior Unsecured Notes and Fixed Rate Mortgages.  We will continue to utilize a combination of borrowings, including term loans, senior unsecured notes and fixed rate mortgages, for future acquisitions and to refinance existing debt. As of December 31, 2025, we had $460.0 million of term loan facilities, $1.950 billion of senior unsecured notes and $198.6 million of fixed rate mortgages outstanding.

For additional detail regarding our Credit Facility, Term Loan Facilities and Senior Unsecured Notes, please see Part II, Item 7, "Liquidity and Capital Resources".

Our outstanding term loan facilities and 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;

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•prepayment penalties and restrictions on refinancing;

•the purchase price of properties or other assets 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, 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.

Equity.  We may issue common shares or preferred shares in public offerings or private placements, or OP units in our Operating Partnership in connection with property acquisitions. On November 19, 2024, we entered into a new At the Market ("ATM") program authorizing, but not obligating, the sale of up to $400.0 million of common shares from time to time. The timing and amount of these offerings, if any, will be determined by our management based on their evaluation of market conditions, share price, legal requirements and other factors. During the year ended December 31, 2025, we did not sell any common shares through the ATM program.

Joint Ventures.  As of December 31, 2025, we owned 262 of our stores through unconsolidated real estate ventures with third parties. Our unconsolidated real estate venture partners typically provide most of the equity capital required for the acquisition of stores owned in these joint ventures. Most joint venture agreements include buy-sell rights, as well as rights of first offer in connection with the sale of stores by the joint venture. We manage the day-to-day operations of the stores owned in our managed joint ventures and participate in major decisions relating to the joint ventures, including the sales of stores or financings by the applicable joint venture.

Sale of Properties.  We have not historically sold a high volume of stores. However, we may sell more stores or interests in stores in the future when we conclude we are holding a non-strategic real estate asset or in response to changing economic, financial or investment conditions. For the year ended December 31, 2025, we sold 15 self storage properties to unaffiliated third parties for net proceeds of $96.9 million. For the year ended December 31, 2024, we sold 40 self storage properties to unaffiliated third parties for net proceeds of $273.1 million and contributed 56 self storage properties to the 2024 Joint Venture for net cash proceeds of $343.7 million.

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.

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, privacy 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.

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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 website. 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 legality of conduct or whether the past or present 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 property owner's or operator's ability to lease, sell or rent such property or to borrow using such property as collateral. Persons who transport, dispose, or arrange for the transport, 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 (including exposure) associated with asbestos-containing materials. 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. Additionally, 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 onsite. 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, health or safety liabilities or costs, including those 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, health and safety 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 and other 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 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 competitors in many of our markets for both tenants and acquisition opportunities include local, regional, and national 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 with these entities for financing opportunities as well as prospective joint venture relationships.

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 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, for our corporate employees, a performance-based bonus incentive plan. As of December 31, 2025, we had 1,458 employees, which includes employees of our property management platform.

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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.nsastorage.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."