Note 12. Related Party Transactions

Self Administration Transaction

On June 28, 2019, we, our Operating Partnership and our TRS entered into a series of transactions, agreements, and amendments to our existing agreements and arrangements with our then-sponsor, SAM, and SmartStop OP Holdings, LLC (“SS OP Holdings”), a subsidiary of SAM, pursuant to which, effective June 28, 2019, we acquired the self storage advisory, asset management and property management businesses and certain joint venture interests of SAM, along with certain other assets of SAM (collectively, the “Self Administration Transaction”).

As a result of the Self Administration Transaction, we became self-managed and succeeded to the advisory, asset management and property management businesses and certain joint ventures previously in place for us, and we acquired the internal capability to originate, structure and manage additional future self storage investment products which would be sponsored by SmartStop REIT Advisors, LLC (“SRA”), our indirect subsidiary.

Our Chief Executive Officer, who is also the Chairman of our board of directors, holds ownership interests in and is an officer of SAM, and other affiliated entities. Previously, certain of our executive officers held ownership interests in and/or were officers of SAM, and other affiliated entities. Accordingly, any agreements or transactions we have entered into with such entities may present a conflict of interest. None of SAM and its affiliates or our directors or executive officers receive any compensation, fees or reimbursements from our Managed REITs, other than with respect to fees and reimbursements in accordance with the Administrative Services Agreement and previously the transfer agent agreement, or as otherwise described in this section.

Former Transfer Agent Agreement

SAM owns 100% of the membership interests of Strategic Transfer Agent Services, LLC, our former transfer agent (“Former Transfer Agent”), which is a registered transfer agent with the SEC. Pursuant to our transfer agent agreement, our Former Transfer Agent provided transfer agent and registrar services to us. These services were substantially similar to what a third party transfer agent would provide in the ordinary course of performing its functions as a transfer agent, including, but not limited to: providing customer service to our stockholders, processing the distributions and any servicing fees with respect to our shares and issuing regular reports to our stockholder.

Fees paid to our Former Transfer Agent included a fixed quarterly fee, one-time account setup fees, monthly open account fees and fees for investor inquiries. In addition, we reimbursed our Former Transfer Agent for all reasonable expenses or other charges incurred by it in connection with the provision of its services to us, and we paid our Former Transfer Agent fees for any additional services that we requested from time to time, in accordance with its rates then in effect.

Effective as of April 29, 2024, we transitioned to a new transfer agent, SS&C GIDS, Inc. In connection with such transfer, we simultaneously terminated the transfer agent agreement with Strategic Transfer Agent Services, LLC. In lieu of a termination fee and in recognition of the additional cost and expenses incurred by our Former Transfer Agent in connection with the transition, we paid a transition fee of $150,000 to Strategic Transfer Agent Services, LLC in May 2024.

Advisory Agreement Fees

Our Managed REIT advisor subsidiaries are or were entitled to receive various fees and expense reimbursements under the terms of the SST VI, SST X, and SSGT III advisory agreements.

SST VI Advisory Agreement

The SST VI advisor provides acquisition and advisory services to SST VI pursuant to an advisory agreement (the “SST VI Advisory Agreement”). In connection with the SST VI private placement offering, SST VI was required to reimburse the SST VI advisor for organization and offering costs from the SST VI private offering pursuant to the SST VI private offering advisory agreement.

Pursuant to the SST VI Advisory Agreement, the SST VI advisor receives acquisition fees equal to 1.00% of the contract purchase price of each property SST VI acquires plus reimbursement of any acquisition expenses that SST VI advisor incurs. The SST VI advisor also receives a monthly asset management fee equal to 0.0625%, which is one-twelfth of 0.75%, of SST VI’s aggregate asset value, as defined. The SST VI advisor is also potentially entitled to receive a disposition fee if a substantial amount of services are performed by the SST VI advisor, as determined by a majority of SST VI’s independent directors, equal to the lesser of 1% of the contract sales price for any properties sold or 50% of the competitive real estate commission; however in no event shall the total real estate commissions paid exceed 6% of the contract sales price.

A subsidiary of our Operating Partnership may also be potentially entitled to a subordinated distribution through its ownership of a special limited partnership in SST VI OP if SST VI (1) lists its shares of common stock on a national exchange, (2) terminates the SST VI Advisory Agreement, (3) liquidates its portfolio, or (4) merges with another entity or enters into an Extraordinary Transaction, as defined in SST VI OP's limited partnership agreement.

The SST VI Advisory Agreement provides for reimbursement of the SST VI advisor’s direct and indirect costs of providing administrative and management services to SST VI. Beginning four fiscal quarters after commencement of SST VI's public offering, which was declared effective March 17, 2022, the SST VI advisor was required to pay or reimburse SST VI the amount by which SST VI’s aggregate annual operating expenses, as defined, exceed the greater of 2% of SST VI’s average invested assets or 25% of SST VI’s net income, as defined, unless a majority of SST VI’s independent directors determine that such excess expenses were justified based on unusual and non-recurring factors.

In connection with the SST VI’s public offering, SST VI was required to reimburse the SST VI advisor for all expenses incurred by SST VI advisor and its affiliates in connection with SST VI’s public offering and its organization, but in no event were such amounts to exceed 15% of the gross offering proceeds raised by SST VI in the terminated or completed offering (including sales commissions, dealer manager fees, stockholder servicing fees and dealer manager servicing fees). If the organization and offering expenses exceeded such limit, within 60 days after the end of the month in which the offering terminated or was completed, pursuant to the terms of the SST VI Advisory Agreement, the SST VI advisor would have had to reimburse SST VI for any excess amounts. SST VI's public offering was closed as of June 30, 2025. In connection therewith, SST VI determined that the organization and offering expenses it incurred did not exceed the limit as described above.

On June 18, 2025, we and various affiliated entities, entered into a Separation and Settlement Agreement (the “Separation Agreement”) with Pacific Oak Holding Group, LLC (“POHG”) and its subsidiary Pacific Oak Capital Markets, LLC, the former dealer manager for SST VI, SSGT III and other affiliated programs (the “Former Dealer Manager”), resulting in (1) the repurchase of the 17.5% non-voting membership interest in the SST VI advisor previously held by POHG, and (2) the termination of a contract whereby services were provided to our programs on our behalf, including the distribution relationship for SST VI, SSGT III and other affiliated programs. In connection with the Separation Agreement, we made a payment to POHG of $3,000,000, which represented full settlement and termination of the various agreements and relationships. Such amount included (i) $650,000 for the termination of the distribution support agreement between SRA and POHG, (ii) $1,850,000 for the repurchase of any and all interests that POHG had in the SST VI advisor, and (iii) $500,000 for severance payments to be made to employees of the Former Dealer Manager. Accordingly, we now own 100% of the SST VI advisor.

The $1,850,000 paid for the repurchase of membership interests in the SST VI advisor was determined based on a pre-existing formula based on distributions over the prior year. This payment was treated as a repurchase of equity and no gain or loss was recognized. The difference between the $1,850,000 paid and the carrying value of the previously existing non-controlling interest was recorded to additional paid-in capital. The separate contract termination costs related to the distribution support agreement and the severance payments were immediately recorded in full to Managed Platform expenses during the year ended December 31, 2025. Excluding the amounts we paid for severance payments, the amounts otherwise paid were based on pre-existing terms included in the underlying agreements.

Subsequent to and as a result of the POHG termination, on June 12, 2025, we, through a subsidiary of our TRS, entered into a new retail distribution and other support arrangement with Orchard Securities, LLC (“Orchard”). Through this relationship, Orchard will distribute certain of our Managed REIT investment programs, including DST offerings and other Managed REIT offerings. We pay Orchard certain fees and expenses as part of the engagement. On September 30, 2025, SST VI commenced a private offering of up to $75.0 million in shares of its Series E Redeemable 8% Preferred Stock, (the “SST VI Preferred Offering”). Pursuant to a managing dealer agreement, Orchard will serve as the managing dealer for the SST VI Preferred Offering and, as part of its compensation under the managing dealer agreement, will be entitled to receive certain fees and expenses in connection with the SST VI Preferred Offering, some of which may be paid by one of our affiliates.

SSGT III Advisory Agreement

The SSGT III advisor provides acquisition and advisory services to SSGT III pursuant to an advisory agreement (the “SSGT III Advisory Agreement”). In connection with the SSGT III private placement offering, which became effective on May 18, 2022, SSGT III is required to reimburse the SSGT III advisor for organization and offering costs from the SSGT III private offering pursuant to the SSGT III Advisory Agreement.

Pursuant to the SSGT III Advisory Agreement, the SSGT III advisor will receive acquisition fees equal to 1.00% of the contract purchase price of each property SSGT III acquires plus reimbursement of acquisition expenses that SSGT III advisor incurs, provided, however, that no reimbursement shall be made for costs of personnel to the extent that such personnel perform services in transactions for which the advisor receives the Acquisition Fee. The SSGT III advisor also receives a monthly asset management fee equal to 0.0625%, which is one-twelfth of 0.75%, of SSGT III’s aggregate asset value, as set forth in the underlying agreements. The SSGT III advisor is also entitled to receive a disposition fee equal to 1.5% of the contract sale price for any properties sold inclusive of any real estate commissions paid to third party real estate brokers. A subsidiary of SSGT III is the sponsor of DSTs and a wholly-owned SSGT III entity also operates the related properties pursuant to a master lease with the respective DST. For certain of such DSTs, upon the successful syndication of the DST offering we will receive an additional 0.60% of the acquisition price related to our assistance with the successful launch of the syndicated investment product. The DST interests are initially owned by SSGT III but are sold to the third parties through

the DST offering sponsored by SSGT III. Given required tax structuring, the control of the DST resides with a signatory trustee, which is affiliated with SSGT III.

Pursuant to the Separation Agreement, POHG is no longer entitled to receive 17.5% of the acquisition fees, asset management fees and disposition fees that the SSGT III advisor earns pursuant to the SSGT III Advisory Agreement.

A subsidiary of our Operating Partnership may also be potentially entitled to various subordinated distributions through its ownership of a special limited partnership in SSGT III’s operating partnership agreement if SSGT III (1) lists its shares of common stock on a national exchange, (2) terminates the SSGT III Advisory Agreement, (3) liquidates its portfolio, or (4) merges with another entity or enters into an Extraordinary Transaction, as defined in the SSGT III operating partnership agreement.

SST X Advisory Agreement

The SST X advisor provides acquisition and advisory services to SST X pursuant to an advisory agreement dated January 31, 2025 (as amended to date, the “SST X Advisory Agreement”). In connection with the SST X private placement offering, which initially commenced on January 31, 2025, the SST X advisor has and will continue to pay for certain organization and offering expenses (other than selling commissions and shareholder servicing fees) and the SST X advisor may pay for certain other operating expenses incurred by SST X through December 31, 2026. SST X is not required to begin to repay such costs until January 2027, at which point SST X must reimburse these costs over 60 months.

Pursuant to the SST X Advisory Agreement, the SST X advisor will not receive acquisition fees, but is entitled to reimbursement of acquisition expenses that the SST X advisor incurs. The SST X advisor is not entitled to receive any disposition fees. The SST X advisor is entitled to a management fee equal to (i) 0.75% of NAV for the Class F-T Common Shares, Class F-D Common Shares, and Class F-I Common Shares, and (ii) 1.25% of NAV for the Class T Common Shares, Class D Common Shares, and Class I Common Shares, in each case, per annum and payable monthly, before giving effect to any accruals by SST X for the management fee, any applicable servicing fees, the performance participation allocation, or any distributions. SST X is currently only offering the Class F-T Common Shares, Class F-D Common Shares and Class F-I Common Shares. Until the first determination of NAV by the SST X advisor, the management fee shall be equal to 0.75% of the per share purchase price of $20.00 for the Class F-T Common Shares, Class F-D Common Shares and Class F-I Common Shares. The SST X Operating Partnership will also pay the SST X advisor a management fee equal to (i) 0.75% of net asset value of the SST X Operating Partnership for the Class F-T OP Units, Class F-D OP Units, and Class F-I OP Units then outstanding held by unitholders other than SST X, and (ii) 1.25% of net asset value of the SST X Operating Partnership for the Class T OP Units, Class D OP Units, and Class I OP units then outstanding held by unitholders other than SST X, in each case, per annum and payable monthly, before giving effect to any accruals for such management fees, any applicable servicing fees, the performance participation allocation, or any distributions by the SST X Operating Partnership. The management fee may be paid, at the SST X advisor’s election, in cash or cash equivalent aggregate NAV amounts of Class E Common Shares or Class E OP Units in Strategic Storage Operating Partnership X, L.P. (the “SST X Operating Partnership” or “SST X OP”). Pursuant to the Separation Agreement, POHG is no longer entitled to receive 17.5% of the asset management fees that SST X advisor earns pursuant to the SST X Advisory Agreement.

In addition, a subsidiary of our Operating Partnership holds a special performance participation interest in the SST X Operating Partnership that entitles it to receive an allocation from the SST X Operating Partnership equal to 10.0% of the Total Return with respect to Class F-T Common Units, Class F-D Units and Class F-I Common Units (12.5% with respect to Class T Units, Class D Units and Class I Units), subject to a 5% Hurdle Amount and a High Water Mark with respect to such class of units, with a Catch-Up (each term as defined in the limited partnership agreement of the SST X Operating Partnership). Such allocation and the related distribution are made annually.

As of December 31, 2025, SST X had sold approximately $2.0 million of its Class F-I Common Shares, and we had a receivable of approximately $2.2 million from SST X related to the costs described above.

On January 23, 2026, SST X re-launched a private offering of up to $600 million in shares of its beneficial interests. Pursuant to a managing dealer agreement, Orchard will now serve as the managing dealer for the SST X private placement offering and, as part of its compensation under the managing dealer agreement, will be entitled to receive certain fees and expenses in connection with the SST X offering, some of which may be paid by one of our affiliates. Additionally, we agreed to re-allow to Orchard 10% of certain fees we are entitled to pursuant to our existing SST X Advisory Agreement and certain

allocations we are entitled to pursuant to the limited partnership agreement of the SST X Operating Partnership, as described above.

Managed REIT Property Management Agreements

Our indirect subsidiaries, SS Growth Property Management III, LLC, Strategic Storage Property Management VI, LLC, and Strategic Storage Property Management X, LLC, (collectively the “Managed REITs Property Managers”), are entitled to receive fees for their services in managing the properties wholly or partially owned by the Managed REITs pursuant to property management agreements entered into between the owner of the property and the applicable Managed REIT’s Property Manager.

The Managed REITs’ Property Managers receive a property management fee equal to 6% of the gross revenues from the properties, generally subject to a monthly minimum of $3,000 per property, plus reimbursement of the costs of managing the properties, and a one-time fee of $3,750 for each property acquired that would be managed by the Managed REITs’ Property Managers. Reimbursable costs and expenses include wages and salaries and other expenses of employees engaged in operating, managing and maintaining such properties. Pursuant to the property management agreements, we through our Operating Partnership employ the on-site staff for the Managed REITs’ properties.

The SST VI, SSGT III, and SST X property managers are entitled to a construction management fee equal to 5% of the cost of a related construction or capital improvement work project in excess of $10,000.

Summary of Fees and Revenue Related to the Managed REITs

We offer tenant insurance or tenant protection programs to customers at our Managed REITs' properties pursuant to which we, as the property manager and majority owner of the Tenant Protection Program joint ventures, are entitled to substantially all of the net revenue attributable to the sale of such tenant programs.

In order to protect our interest in receiving these revenues in light of the fact that the Managed REITs control the properties, we and the Managed REITs transferred our respective rights in such arrangements to a joint venture entity owned 99.9% by us through a TRS subsidiary and 0.1% by the Managed REIT. Under the terms of the operating agreements of the joint venture entities, we receive 99.9% of the net revenues generated from such Tenant Protection Programs and the Managed REIT receives the other 0.1% of such net revenues.

Reimbursable costs from Managed REITs includes reimbursement of SST VI, SST X, and SSGT III's Advisors’ certain direct and indirect costs of providing administrative and management services to the Managed REITs. Additionally, reimbursable costs includes reimbursement pursuant to the property management agreements for reimbursement of certain costs of managing the Managed REITs’ properties, including wages and salaries and other expenses of employees engaged in operating, managing and maintaining such properties.

As of December 31, 2025 and 2024, we had receivables due from the Managed REITs totaling approximately $23.4 million, and $16.7 million, respectively. Such amounts are included in investments in and advances to Managed REITs in our consolidated balance sheets. Such amounts included unpaid amounts relative to the above table, in addition to other direct routine reimbursable expenditures of the Managed REITs that we directly funded.

Investments in and advances to SST VI OP

Equity Investments

On March 10, 2021, SmartStop OP made an investment of $5.0 million in SST VI OP, in exchange for common units of limited partnership interest in SST VI OP. Additionally, a subsidiary of SmartStop OP owns a special limited partnership interest (the “SST VI SLP”) in SST VI OP.

For the years ended December 31, 2025, 2024 and 2023, we recorded a loss related to our equity interest, excluding our preferred investment discussed below, in SST VI OP of approximately $0.5 million, $0.9 million and $0.9 million, respectively, and received distributions in the amount of approximately $0.3 million, $0.3 million and $0.3 million, respectively, excluding distributions received related to the Series D Preferred Units, defined below.

On September 4, 2025, we, through one our subsidiaries entered into a preferred unit purchase agreement with SST VI OP (the “Series D Preferred Unit Purchase Agreement”) for up to 1,400,000 Series D cumulative redeemable preferred units (“Series D Preferred Units”), in consideration for up to $35.0 million. Distributions on the Series D Preferred Units of SST VI OP are cumulative from the date of issuance and are payable monthly in arrears. Distributions are payable at a rate of: (a) 6% per annum from the date of issuance until the second anniversary after the date of issuance; (b) 7% per annum commencing the day following the second anniversary after the date of issuance until the third anniversary after the date of issuance; (c) 8% per annum commencing the day following the third anniversary after the date of issuance until the fourth anniversary after the date of issuance; and (d) 9% per annum thereafter. The Series D Preferred Unit Purchase Agreement provides that the purchase price for the Series D Preferred Units shall be equal to $25 per share. The Series D Preferred Units require an investment fee equal to 1.0% of the amount invested at any closing.

On September 4, 2025, we made an initial investment of $5.0 million or 200,000 Series D Preferred Units at a purchase price of $25.00 per unit. During September 2025, we made additional purchases of 800,000 Series D Preferred Units for an additional $20.0 million. SST VI used certain of the funds received from our investment in the Series D Preferred Units to repay approximately $19.3 million in receivable balances to us.

During the three months ended December 31, 2025, through a series of transactions, we purchased an additional 400,000 Series D Preferred Units at a purchase price of $25.00 per unit, for a total of $10.0 million. As of December 31, 2025, we had purchased an aggregate of 1.4 million Series D Preferred Units for $35.0 million. As such, we were no longer required to make any further purchases of Series D Preferred Units in connection with the Series D Preferred Unit Purchase Agreement, as discussed above.

For the year ended December 31, 2025 we recorded income of approximately $0.5 million from our investment in the Series D Preferred Units.

Sponsor Funding Agreement

On November 1, 2023, SRA, a subsidiary of our Operating Partnership, entered into a Sponsor Funding Agreement with SST VI and SST VI OP, in connection with certain changes to the public offering of SST VI.

Pursuant to the Sponsor Funding Agreement, SRA, as sponsor of the SST VI offering, had agreed to fund the payment of (i) the upfront 3% sales commission for the sale of Class Y shares sold in the SST VI offering, (ii) the upfront 3% dealer manager fee for the Class Y shares sold in the SST VI offering, and (iii) the estimated 1% organization and offering expenses for the sale of Class Y shares and Class Z shares sold in the SST VI offering. SRA had also agreed to reimburse SST VI in cash to cover the dilution from certain one-time stock dividends which were issued by SST VI to existing stockholders in connection with the sponsor funding changes to the SST VI offering. On December 15, 2023, we paid SST VI approximately $6.6 million for the reimbursement of the aforementioned stock dividend.

In consideration for SRA providing the funding for the front-end sales load and the cash to cover the dilution from the stock dividends described above, SST VI OP issued a number of Series C Units to SRA equal to the dollar amount of such funding divided by the then-current offering price for the Class Y shares and Class Z shares sold in the SST VI offering, which was initially $9.30 per share. Pursuant to the Sponsor Funding Agreement, SRA reimbursed SST VI monthly for the applicable front-end sales load it had agreed to fund, and SST VI OP issued the Series C Units on a monthly basis upon such reimbursement.

On November 1, 2023, SRA entered into Amendment No. 3 to the Second Amended and Restated Limited Partnership Agreement of SST VI OP with SST VI and SST VI OP containing, among other things, the terms of the Series C Units. The Series C Units shall initially have no distribution, liquidation, voting, or other rights to participate in SST VI OP unless and until such Series C Units are converted into Class A units of SST VI OP. The Series C Units shall automatically convert into class A units on a one-to-one basis upon SST VI’s disclosure of an estimated net asset value per share equal to at least $10.00 per share for each Class of SST VI shares of common stock, including the Class Y shares and Class Z shares, calculated net of the Series C Units to be converted.

On August 7, 2024, SST VI declared an estimated net asset value per share of $10.00. Since the Series C Units that could be converted would result in the net asset value falling below $10.00 per share, none of the Series C Units we owned were converted into Class A units of SST VI OP, and thereafter our future purchases were to be determined based on the current estimated net asset value at such time. Subsequent to SST VI declaring an estimated net asset value of $10.00 per share, the number of Series C Units we received in exchange for funding the front-end sales load of the sale of SST VI's Class Y and Class Z shares was calculated as the dollar amount of such sponsor funding divided by the then current offering price of $10.00 per share for such Class Y and Z shares.

As of June 30, 2025, SST VI closed the primary portion of its public offering. The Sponsor Funding Agreement was terminated immediately in connection with the closedown of SST VI’s primary offering. In accordance therewith, we have no further funding obligation in connection with the Sponsor Funding Agreement.

As of December 31, 2025, we had incurred approximately $10.2 million in connection with the now terminated Sponsor Funding Agreement, representing approximately 1.1 million Series C Units issued by SST VI OP. During the year ended December 31, 2025 we incurred approximately $0.9 million.

Debt Investments

On June 13, 2023 SmartStop OP entered into a promissory note agreement with SST VI OP ( the “SST VI Note”), where SST VI OP borrowed $15.0 million. Interest on the loan accrued at SOFR plus 3.0%. Payments on the SST VI Note are interest only. The loan was extended on December 8, 2023 to December 31, 2024 at the borrower's option, and as such, the interest rate on the loan increased to SOFR plus 4.0%, and a fee equal to 0.25% of the outstanding principal balance was due as a result of SST VI exercising the extension option. The SST VI Note required a commitment fee equal to 1.0% of the aggregate principal amount of the loan.

On June 28, 2024, the SST VI Note was amended to expand the borrowing capacity up to $25.0 million and further extend the maturity date from December 31, 2024 to December 31, 2025. On July 29, 2024, SST VI borrowed an additional $8.0 million on the SST VI Note. On July 29, 2025, SST VI borrowed an additional $2.0 million on the SST VI Note.

On December 22, 2025, the SST VI Note was further amended whereby the ultimate maturity date was extended to June 30, 2027. Additionally, interest on this note began accruing at SOFR plus 3.5%, effective January 1, 2026 in connection with such amendment.

Investments in and advances to SSGT III OP

Equity Investments

On August 29, 2022, SmartStop OP made an investment of $5.0 million in SS Growth Operating Partnership III, L.P., the operating partnership of SSGT III (“SSGT III OP”), in exchange for common units of limited partnership interest in SSGT III OP. Additionally, a subsidiary of SmartStop OP owns a special limited partnership interest (the “SSGT III SLP”) in SSGT III OP.

For the years ended December 31, 2025, 2024 and 2023, we recorded a loss related to our equity interest in SSGT III OP of approximately $0.6 million, $0.6 million and $0.7 million, respectively, and received distributions in the amount of approximately $0.3 million, $0.3 million and $0.3 million, respectively.

Debt Investments

On July 31, 2024, our Operating Partnership provided a bridge loan to an indirect wholly-owned subsidiary of SSGT III for $20.0 million (the “SSGT III Bridge Loan”) to facilitate SSGT III’s acquisition of two self storage facilities. Through a series of payments, during the three months ended March 31, 2025, SSGT III and its subsidiaries repaid all amounts

outstanding on the SSGT III Bridge Loan, in accordance with the terms of the SSGT III Bridge Loan, no further draws were permitted thereafter.

On December 16, 2024, a subsidiary of SSGT III entered into a promissory note with our Operating Partnership for a $7.0 million loan (the “SSGT III Promissory Note”), the entire principal amount of the loan was disbursed to SSGT III on such date. Pursuant to this note, interest on the SSGT III Promissory Note accrued at a variable rate equal to SOFR plus 3.0% per annum. Payments on the SSGT III Promissory Note were interest only, and it had an initial maturity date of March 17, 2025. The SSGT III Promissory Note required a commitment fee equal to 0.50% of the amount drawn at closing of the SSGT III Promissory Note. During the three months ended March 31, 2025, SSGT III and it subsidiaries repaid all amounts outstanding on the SSGT III Promissory Note, including accrued interest.

On June 3, 2025, a subsidiary of SSGT III entered into a promissory note with our Operating Partnership for a loan of up to $25.0 million (the “SSGT III Promissory Note II”). On June 5, 2025, $4.0 million was initially drawn on the loan and disbursed to SSGT III. Interest on the SSGT III Promissory Note II accrued at a variable rate equal to SOFR plus 3.0% per annum. Payments on the SSGT III Promissory Note II were interest only until maturity. This note had an initial maturity date of December 31, 2025, with two optional extensions, each for 6 months, subject to certain conditions. The SSGT III Promissory Note II required a commitment fee equal to 0.50% of the amount drawn at such time. Since the initial draw, SSGT III made a series of additional draws. In November 2025, through a series of payments, SSGT III fully repaid the outstanding balance on the SSGT III Promissory Note II. No further draws were permitted in connection with such note.

On June 24, 2025, our Operating Partnership fully funded a secured term loan pursuant to a promissory note entered into by a subsidiary of SSGT III for a $25.0 million loan (the “SSGT III Secured Note”). Interest on the SSGT III Secured Note accrued at a variable rate equal to SOFR plus 3.0% per annum. Payments on the SSGT III Secured Note were interest only until maturity. This note has an initial maturity date of December 31, 2025, with two optional extensions, each for 6 months, subject to certain conditions. The SSGT III Secured Note required a commitment fee equal to 0.50% of the amount drawn at such time. In September 2025, SSGT III paid down $12.0 million on the SSGT III Secured Note. In November 2025, SSGT III fully repaid the outstanding balance on the SSGT III Secured Note. No further draws were permitted in connection with such note.

On November 13, 2025, our Operating Partnership provided a bridge loan to Blue Door AM I, LLC, an indirect wholly-owned subsidiary of SSGT III for $15.0 million (the “SSGT III-Blue Door III Bridge Loan”) in order to capitalize a Delaware statutory trust. The SSGT III-Blue Door III Bridge Loan required a commitment fee equal to 0.50% of the original principal amount of the loan. Interest on the SSGT III-Blue Door III Bridge Loan accrues at a variable rate equal to SOFR plus 3.0% per annum. As such interest accrues it will be added to the principal balance outstanding on each payment date until the loan is fully repaid. The loan has an initial maturity date of November 13, 2026, with a one-time extension option of 6 months, extending the maturity to April 13, 2027, subject to certain conditions. An extension fee of 0.25% of the principal indebtedness as of the extension date is due if such extension option is exercised, and the spread on the interest rate increases to 4.0% upon exercising the extension option. The loan agreement requires the borrower to make a prepayment on the SSGT III-Blue Door III Bridge Loan in an amount equal to 80% of the equity proceeds the borrower receives from its equity issuances (each, a “Bridge Loan Prepayment”). Each Bridge Loan Prepayment is due on the next occurring payment date following the borrower's receipt issuance proceeds.

On December 18, 2025, SSGT III's taxable REIT subsidiary entered into a loan with KeyBank National Association (“KeyBank”) in the amount of $25.0 million (the “KeyBank-SSGT III Bridge Loan”), which matures on June 18, 2026, subject to a six-month extension option. The KeyBank-SSGT III Bridge Loan has curtailment provisions that the outstanding loan balance must be no greater than $7.5 million, $5.0 million and $2.5 million as of March 31, April 30 and May 31, 2026, respectively. As of February 17, 2026, the outstanding balance of the KeyBank-SSGT III Bridge Loan was $5.9 million. In connection with this loan, we entered into a subordination and standstill agreement with KeyBank, whereby, among other things, the SSGT III-Blue Door III Bridge Loan became subordinate to the KeyBank-SSGT III Bridge Loan and all rights to payments under the SSGT III-Blue Door III Bridge Loan, including the Bridge Loan Prepayment, became subordinated to KeyBank's rights to payment under the KeyBank-SSGT III Bridge Loan.

Investments in and advances to DSTs Sponsored by SSGT III

On November 13, 2025 a subsidiary of ours funded three non-recourse mortgage loans to indirect subsidiaries of SSGT III for approximately $24.2 million, collectively. Each of these three loans (the “BD III DST Mortgage Loans”) have an initial maturity date of November 13, 2032. The BD III DST Mortgage Loans were funded net of approximately $0.4 million or 1.75% in fees owed to us for structuring and origination. Payments are due monthly in arrears, are interest only until maturity, and accrue at a fixed rate of 5.0% per annum. Subject to certain conditions, the DST borrowers have two extension options, each for a one year term, with the second extension ultimately requiring full principal repayment in November 2034. If the DST borrowers choose to exercise the extension option, the interest rate in effect changes to a fixed rate calculated as the then current 30-day average SOFR rate plus a spread of 1.50%. Such calculated rate in effect as of the exercise of the extension option would be fixed until the ultimate maturity of the BD III DST Mortgage Loans. The DST borrowers may prepay the loans at any point in time, subject to the following premium schedule, expressed as a percentage of the then outstanding principal balance prepaid: (i) 5% on or before November 13, 2026, (ii) 3% between November 13, 2026 and November 13, 2028, (iii) 1% between November 13, 2028 and November 13, 2030, and (iv) 0% on or after November 13, 2030.

On January 28, 2026, a subsidiary of ours funded three non-recourse mortgage loans to indirect DST subsidiaries of SSGT III for approximately $16.0 million, collectively. Each of these three loans (the “BD IV DST Mortgage Loans”) have an initial maturity date of January 28, 2033. The BD IV DST Mortgage Loans were funded net of approximately $0.5 million or 3.0% in fees owed to us for structuring and origination. Payments are due monthly in arrears, are interest only until maturity, and accrue at a fixed rate of 5.0% per annum. Subject to certain conditions, the DST borrowers have two extension options, each for a one year term, with the second extension ultimately requiring full principal repayment on January 28, 2035. If the DST borrowers choose to exercise the extension option, the interest rate in effect changes to a fixed rate calculated as the then current 30-day average SOFR rate plus a spread of 1.50%. Such calculated rate in effect as of the exercise of the extension option would be fixed for the extension term. A 0.2% extension fee would become due upon each extension option being exercised. The DST borrowers may prepay the loans at any point in time, subject to the following premium schedule, expressed as a percentage of the then outstanding principal balance prepaid: (i) 5% on or before January 27, 2027, (ii) 3% between January 28, 2027 and January 27, 2029, (iii) 1% between January 28, 2029 and January 27, 2031, and (iv) 0% on or after January 28, 2031.

We serve as the property manager for the properties owned by the DSTs that are leased pursuant to a master lease by a SSGT III subsidiary, which pursuant to the lease is required to pay rent to the DST equal to the required debt service. Such requirement is further supported by a minimum capital requirement of the SSGT III lessor entity, initially further supported by a guaranty from the SSGT III operating partnership of such required capital. As of December 31, 2025, SSGT III had sponsored and initiated the syndication of DST interests to retail investors for such DST programs, covering eight properties.

The above SSGT III DST syndicated offerings were in various stages of completion. We serve as the property manager for each property owned by such DSTs.

The following table summarizes the carrying value of our investments in and advances to DSTs Sponsored by SSGT III for the periods presented (dollars in thousands):

Investments in and advances to SST X OP

Equity Investments

SmartStop Storage Advisors, LLC (“SSA”), a subsidiary of SmartStop OP, made two contributions of $1,000 to SST X OP, in exchange for common units of limited partnership interest in SST X OP, one on January 14, 2025 in connection with the formation of SST X OP and the other on June 27, 2025 in connection with the entry into the advisory agreement and the first amended and restated limited partnership agreement of SST X OP, in which SSA was granted a special limited partnership interest in SST X OP. Similarly, the SST X advisor made a $1,000 investment in common shares on January 28, 2025 in connection with the formation of SST X.

On October 29, 2025, we, through one our subsidiaries entered into a preferred unit purchase agreement with SST X OP for 72,000 series A cumulative preferred units (the “Series A Preferred Units”), for $1.8 million. Distributions on the Series A Preferred Units of SST X OP are cumulative from the date of issuance and are payable monthly in arrears. Distributions are payable at a rate of: (a) 6% per annum from the date of issuance until the second anniversary after the date of issuance; (b) 7% per annum commencing the day following the second anniversary after the date of issuance until the third anniversary after the date of issuance; (c) 8% per annum commencing the day following the third anniversary after the date of issuance until the fourth anniversary after the date of issuance; and (d) 9% per annum thereafter. The Series A Preferred Units require an investment fee equal to 1.0% of the amount invested at any closing. As of December 31, 2025, we had purchased an aggregate of 72,000 Series A Preferred Units for $1.8 million.

During the year ended December 31, 2025, we recorded approximately $0.1 million of income from our investment in the SST X Series A Preferred Units.

On October 30, 2025, we sold the Murfreesboro, Tennessee property to SST X for approximately $7.9 million. See Note 3 – Real Estate Facilities for additional information.

Administrative Services Agreement

On June 28, 2019, we along with our Operating Partnership, our TRS and SmartStop Storage Advisors, LLC (collectively, the “Company Parties”) entered into an Administrative Services Agreement with SAM (the “Administrative Services Agreement”), which, as amended, requires that the Company Parties will be reimbursed for providing certain operational and administrative services to SAM which may include, without limitation, accounting and financial support, IT support, HR support, advisory services and operations support, and administrative support and other miscellaneous reimbursements as set forth in the Administrative Services Agreement and SAM will be reimbursed for providing certain operational and administrative services to the Company Parties which may include, without limitation, due diligence support, marketing, fulfillment and offering support, events support, insurance support, and administrative and facilities support. SAM and the Company Parties will reimburse one another based on the actual costs of providing their respective services.

For the years ended December 31, 2025, 2024 and 2023, we incurred reimbursements payable to SAM under the Administrative Services Agreement of approximately $0.7 million, $0.8 million and $0.5 million, respectively, which were recorded in the Managed Platform expenses line item in our consolidated statements of operations.

We recorded reimbursements from SAM of approximately $0.6 million, $0.2 million and $0.7 million for the years ended December 31, 2025, 2024 and 2023, respectively, related to services provided to SAM, which were included in Managed Platform revenue in our consolidated statements of operations.

As of December 31, 2025 and 2024, a receivable of approximately $0.4 million and a receivable of approximately $0.1 million, respectively, was due from SAM related to the Administrative Services Agreement.

See Note 6 – Investments in Unconsolidated Real Estate Ventures for additional information regarding other equity method investees deemed to be a related party, given they are accounted for as equity method investments.