Annual Report of Employee Stock Purchase/Savings Plan (Form 11-K)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 11-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE

ACT OF 1934

For the fiscal year ended December 31, 2025

OR

 TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Commission File Number 000-13292

McGRATH RENTCORP

EMPLOYEE STOCK OWNERSHIP AND 401(K) PLAN

McGRATH RENTCORP

5700 Las Positas Road

Livermore, California 94551-7800

TABLE OF CONTENTS

Plan Administrator and Plan Participants

McGrath RentCorp Employee Stock Ownership and 401(k) Plan

Opinion on the financial statements

We have audited the accompanying statements of net assets available for benefits of McGrath RentCorp Employee Stock Ownership and 401(k) Plan (the "Plan") as of December 31, 2025 and 2024, the related statement of changes in net assets available for benefits for the year ended December 31, 2025, and the related notes (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 2025 and 2024, and the changes in net assets available for benefits for the year ended December 31, 2025 in conformity with accounting principles generally accepted in the United States of America.

Basis for opinion

These financial statements are the responsibility of the Plan's management. Our responsibility is to express an opinion on the Plan's financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) ("PCAOB") and are required to be independent with respect to the Plan in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Plan is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Plan's internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Supplemental information

The supplemental schedule, schedule of assets (held at end of year) as of December 31, 2025, ("supplemental information") has been subjected to audit procedures performed in conjunction with the audit of the Plan's financial statements. The supplemental information is the responsibility of the Plan's management. Our audit procedures included determining whether the supplemental information reconciles to the financial statements or the underlying accounting and other records, as applicable, and performing procedures to test the completeness and accuracy of the information presented in the supplemental information. In forming our opinion on the supplemental information, we evaluated whether the supplemental information, including its form and content, is presented in conformity with the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income

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Security Act of 1974. In our opinion, the supplemental information is fairly stated, in all material respects, in relation to the financial statements as a whole.

/s/ GRANT THORNTON LLP

We have served as the Plan's auditor since 2011.

Philadelphia, Pennsylvania
June 4, 2026

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MCGRATH RENTCORP

EMPLOYEE STOCK OWNERSHIP AND 401(k) PLAN

Statements of Net Assets Available for Benefits

The accompanying notes are an integral part of these financial statements.

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MCGRATH RENTCORP

EMPLOYEE STOCK OWNERSHIP AND 401(k) PLAN

Statement of Changes in Net Assets Available for Benefits

The accompanying notes are an integral part of this financial statement.

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MCGRATH RENTCORP

EMPLOYEE STOCK OWNERSHIP AND 401(k) PLAN

Notes to Financial Statements

NOTE 1 - DESCRIPTION OF THE PLAN

The following description of the McGrath RentCorp Employee Stock Ownership and 401(k) Plan (the "KSOP" or "Plan") provides only general information. Participants should refer to the KSOP plan document for a more complete description of the KSOP's provisions.

General

The KSOP is intended to qualify as an employee stock ownership plan as defined in Section 4975(e)(7) of the Internal Revenue Code (the "Code"), a stock bonus plan under Section 401(a) of the Code and a cash or deferred plan under Section 401(k) of the Code and is subject to the provisions of the Employee Retirement Income Security Act of 1974, as amended (ERISA).

McGrath RentCorp (the "Company") created a trust to hold Plan assets, effective August 1, 2012, and appointed Charles Schwab Bank as the Trustee of that trust. Schwab Retirement Plan Services serves as the record keeper to maintain the individual accounts of each of the Plan's participants.

The Plan documents provide for the ability for the Plan to borrow, with a portion of the Company shares held by the Plan used as collateral. There have been no borrowings in the past and the Company's Board of Directors currently has no plans to undertake such a transaction.

Significant provisions and amendments to the Plan are summarized in these Notes to Financial Statements.

Administration of the Plan

The KSOP's assets are held by the Trustee of the KSOP. All contributions are held by the Trustee, which invests cash received, interest and dividend income per the instruction from participants and makes distributions to participants. The Company is designated as the Plan Administrator within the meaning of ERISA.

Eligibility

All employees of the Company and any affiliate which had adopted the KSOP who are 21 years or older and have at least two months of eligibility service for elective deferral contribution are eligible to participate in the KSOP except:

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Participant Accounts

The KSOP is a defined contribution plan under which a separate individual account is established for each participant. Each participant account is credited with the participants elective 401(k) contribution as well as an allocation of the Company's contribution, earnings or losses related to the net assets in their accounts, and an allocation of forfeitures of terminated participants' unvested accounts.

Contributions

Eligible employees may elect to defer a percentage of his or her pre-tax and after-tax compensation, not to exceed the statutory limit. Employees who have completed a minimum of 1,000 hours are also entitled to a Safe Harbor matching contribution, as defined in the Code, from the Company equal to 100% of the employee's deferral into the KSOP, up to a maximum of 4% of the employee's eligible compensation. The Company directs 50% of the Safe Harbor Match per participant's investment instructions and 50% to the MGRC Unitized Stock Fund with the option to transfer such amounts as the participant directs after it is contributed. The Company may also make additional discretionary contributions, which, if made, are allocated based on the units held by each eligible participant. For this purpose, a participant is considered to have one unit for each $1,000 of compensation during the plan year plus two units for each year of service. Highly compensated employees do not receive unit credit for any years of service. Trust income or loss is allocated based on the respective account balances of participants. There were no discretionary contributions to the plan in 2025.

Vesting

A participant receives one year of credited service for vesting purposes at the end of each Plan year in which he or she completes 1,000 hours of service, starting with their first hour of employment, and regardless of whether or not he or she completes twelve months of service during the first year. A participant's account balance is 100 percent vested upon death, disability, or normal retirement (age 65). A participant is always fully (100 percent) vested in his or her salary reduction contributions, employer Safe Harbor matching contributions, and rollover contributions, plus actual earnings thereon. In the event the Company elects to make a discretionary non-elective contribution, the participant vests in his or her contributions over a six year graded vesting schedule as follows:

The vesting schedule will be accelerated and the Company's contributions and KSOP allocations will be modified if the KSOP becomes a "top-heavy plan" under the Code.

Forfeitures

Any forfeited KSOP benefits are allocated in the same manner as the Company's contributions among the accounts of participants who remain employed throughout the year and have worked a minimum number of hours or whose employment has terminated due to death, disability or normal

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retirement during that year. Forfeitures can be used to pay plan administrative expenses, reduce employer contributions, or increase benefits to participants.

There were no forfeitures of common stock and cash for the year ended December 31, 2025. Forfeiture funds were not used in the 2025 plan year, the balance of unallocated forfeitures at December 31, 2025 and 2024 was $51,945 and $47,910, respectively.

Notes Receivable from Participants

Participants may borrow from their fund accounts a minimum of $1,000 up to a maximum equal to the lesser of $50,000, or 50% of their vested account balance. Loan terms generally range from one to five years, but can be up to 15 years for the purchase of a principal residence. Loans are issued at a fixed interest rate, which is the prevailing rate for a similar loan at the time of issuance. A participant may not have more than three loans outstanding at any time. The loans are secured by the balance in the participant's account. A participant's account is charged monthly interest on each outstanding loan balance. Principal and interest is paid ratably through payroll deductions. Upon termination of employment, all loans will immediately become payable. If a loan is not repaid within a reasonable time following termination of employment, the loan will be recorded as a distribution against the participant's vested account balance.

Payment of Benefits

In the event of a termination of service due to death, disability or retirement, benefits become payable. Benefits are normally paid in the form of a periodic distribution or, if the participant so elects, in a lump sum. For account balances below $7,000, a lump sum may be paid out without regard to the participant's election. Distributions are made in cash or, if the participant elects, in the form of Company common stock.

The Company has determined that cash dividends paid by the Company on shares of the Company's Common Stock held by the KSOP's McGrath RentCorp Unitized Stock Fund (the "Unitized Stock Fund") are to be paid into the fund and the participant elects whether the dividends are paid out to the participant or reinvested within the plan. The default election is reinvestment within the plan. The Company has the right to revoke this decision at any time.

Voting Rights

Each participant is entitled to exercise voting rights attributable to the Company shares allocated to his or her account through his or her holdings in the Unitized Stock Fund and is notified by the Trustee prior to the time that such rights are to be exercised. The Trustee is required to vote any unallocated shares held by the KSOP and any allocated shares for which instructions have not been given by a participant in the same proportion as the shares for which voting instructions have been received, subject to the power, responsibility and obligation of the Plan Administrator to direct the Trustee to act with respect to the voting of such shares in a different manner, if the Plan Administrator determines that such action is consistent with and/or required by its fiduciary obligations under ERISA.

Plan Termination

Although the KSOP is intended to be permanent in nature, the Company may terminate the KSOP at its discretion, subject to the provisions of ERISA. If the KSOP is terminated, participants will become fully vested in their accounts.

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The asset's or liability's fair value measurement level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation techniques used need to maximize the use of observable inputs and minimize the use of unobservable inputs.

The following is a description of the valuation methodologies used by the Plan for assets measured at fair value. There have been no changes to the methodologies used as of December 31, 2025 and 2024.

Mutual Funds

Valued at the daily closing price as reported by the fund. Mutual funds held by the Plan are open-end mutual funds that are registered with the Securities and Exchange Commission. These funds are required to publish their daily net asset value ("NAV") and to transact at that price. The mutual funds held by the Plan are actively traded.

McGrath RentCorp Unitized Stock Fund ("Fund")

The Fund consists of the Company's common stock and short-term cash which provides liquidity for daily trading. The Company's common stock is valued at the quoted market price from a national securities exchange and the short-term cash investments are held in a money market mutual fund and are valued at fair value based on the NAV per share. A market-based NAV per share is calculated on a periodic basis. Shares can be redeemed on a same day basis but only directly from the Fund.

Collective Investment Trusts

The Plan has investments in Collective Investment Trusts (CITs) managed by numerous investment funds. The CITs are valued at the NAV as provided by the administrators of the fund. The NAV is used as the practical expedient to estimate fair value. The NAV is based on the value of the underlying assets of the fund, less liabilities, and then divided by the number of units outstanding.

Brokerage Account

A participant-directed brokerage account allows an investor to buy or sell investments such as cash, stocks, unit investment trusts and mutual funds. The fair value of the brokerage account is the aggregation of the fair value of the underlying assets, all of which are actively traded.

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Assets at fair value as of December 31, 2025:

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SUPPLEMENTAL SCHEDULE

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MCGRATH RENTCORP

EMPLOYEE STOCK OWNERSHIP AND 401(k) PLAN

EIN 94-2579843

Plan Number 001

Schedule H, line 4i - Schedule of Assets (Held at End of Year)

December 31, 2025

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Exhibit

Signatures

Pursuant to the requirements of the Securities Exchange Act of 1934, the Plan Administrator of the McGrath RentCorp Employee Stock Ownership and 401(k) Plan has duly caused this annual report to be signed on its behalf by the undersigned thereunto duly authorized.

Date: June 4, 2026

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