# EDGAR Filing Document

**Accession Number:** 0001766368
**File Stem:** 0001558370-25-008770
**Filing Date:** 2025-6
**Character Count:** 31825
**Document Hash:** 22ce0fa6bf6697ca39ab3687421b516b
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001558370-25-008770.hdr.sgml**: 20250620

**ACCESSION NUMBER**: 0001558370-25-008770

**CONFORMED SUBMISSION TYPE**: 11-K

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20241231

**FILED AS OF DATE**: 20250620

**DATE AS OF CHANGE**: 20250620

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Mayville Engineering Company, Inc.
- **CENTRAL INDEX KEY:** 0001766368
- **STANDARD INDUSTRIAL CLASSIFICATION:** METAL FORGING & STAMPINGS [3460]
- **ORGANIZATION NAME:** 04 Manufacturing
- **EIN:** 390944729
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 11-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38894
- **FILM NUMBER:** 251061162

**BUSINESS ADDRESS:**
- **STREET 1:** 715 SOUTH STREET
- **CITY:** MAYVILLE
- **STATE:** WI
- **ZIP:** 53050
- **BUSINESS PHONE:** 920-387-4500

**MAIL ADDRESS:**
- **STREET 1:** 715 SOUTH STREET
- **CITY:** MAYVILLE
- **STATE:** WI
- **ZIP:** 53050

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Mayville Engineering Comapny, Inc.
- **DATE OF NAME CHANGE:** 20190130

[**Table of Contents**](#TOC)

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**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

------

**FORM 11-K**

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**FOR ANNUAL REPORTS OF EMPLOYEE STOCK PURCHASE, SAVINGS**

**AND SIMILAR PLANS PURSUANT TO SECTION 15(d) OF**

**THE SECURITIES EXCHANGE ACT OF 1934**

**(Mark One)**

☒ **ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934** 

**For the fiscal year ended December 31, 2024**

**OR**

☐ **TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934** 

**For the transition period from __________ to __________**

**Commission File Number 001-38894**

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&nbsp;&nbsp;&nbsp;&nbsp;A. Full title of the plan and the address of the plan, if different from that of the issuer named below:

**Mayville Engineering Company, Inc.**

**401(k) Plan**

&nbsp;&nbsp;&nbsp;&nbsp;B. Name of issuer of the securities held pursuant to the plan and the address of its principal executive office:

**Mayville Engineering Company, Inc.**

**135 S. 84**<sup>th</sup> **Street, Suite 300**

**Milwaukee, Wisconsin 53214**

------

[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc. 401(k) Plan**

**Table of Contents**

---

| | |
|:---|:---|
| [REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM](#Independent_Report) | 1 |
| FINANCIAL STATEMENTS |  |
| [Statements of Net Assets Available for Benefits as of December 31, 2024 and 2023](#StatementsofNetAssetsAvailableforBenefit) | 2 |
| [Statement of Changes in Net Assets Available for Benefits for the Year Ended December 31, 2024](#StatementofChangesinNetAssetsAvailablefo) | 3 |
| [Notes to Financial Statements](#NotesToFinancials) | 4 |
| SUPPLEMENTAL SCHEDULE—\* |  |
| [Form 5500, Schedule H, Part IV, Line 4i—Schedule of Assets (Held at End of Year) as of December 31, 2024](#Schedule_of_Assets_5500) | 9 |
| [EXHIBIT](#ExhibitIndex_552028) | 10 |
| [SIGNATURE](#SIGNATURES_579520) | 11 |
| [23.1 Consent of Independent Registered Public Accounting Firm](tmb-20241231xex23d1.htm) |  |

---

\*Other supplementary schedules required by Section 2520.103-10 of the Department of Labor's Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974 have been omitted because they are not applicable.

------

[**Table of Contents**](#TOC)

#### REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
Plan Administrative Committee, Plan Administrator, and Plan Participants

Mayville Engineering Company, Inc. 401(k) Plan

#### Opinion on the Financial Statements
We have audited the accompanying statements of net assets available for benefits of the Mayville Engineering Company, Inc. 401(k) Plan (the Plan) as of December 31, 2024 and 2023, and the related statement of changes in net assets available for benefits for the year ended December 31, 2024, 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, 2024 and 2023, and the changes in net assets available for benefits for the year ended December 31, 2024, 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 information in the accompanying Form 5500, Schedule H, Part IV, Line 4i - Schedule of Assets (Held at End of Year) as of December 31, 2024 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 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/ Wipfli LLP

We have served as the Plan's auditor since 2020.

Minneapolis, Minnesota

June 20, 2025

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[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Statements of Net Assets Available for Benefits**

*(in thousands)*

---

| | | |
|:---|:---|:---|
|  | **December 31,**  | **December 31,**  |
|  | **2024** | **2023** |
| **Assets:** |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Investments at fair value: |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Mutual funds | $122967 | $95961 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Collective trust fund |  | 5565 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Corporate common stock | 33106 | 48075 |
| &nbsp;&nbsp;**Net assets available for benefits** | $156073 | $149601 |

---

See Notes to Financial Statements

------

[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Statement of Changes in Net Assets Available for Benefits**

*(in thousands)*

---

| | |
|:---|:---|
|  | **Year Ended**<br>**December 31, 2024** |
| **Additions:** |  |
| &nbsp;&nbsp;Investment income: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Net appreciation in fair value of investments | $18515 |
| &nbsp;&nbsp;&nbsp;&nbsp;Interest and dividends | 2183 |
| &nbsp;&nbsp;Total investment income | 20698 |
| &nbsp;&nbsp;Contributions: |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Participants | 9362 |
| &nbsp;&nbsp;&nbsp;&nbsp;Company | 3384 |
| &nbsp;&nbsp;&nbsp;&nbsp;Rollovers | 4679 |
| &nbsp;&nbsp;Total contributions | 17425 |
| Total additions | 38123 |
| **Deductions:** |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Benefits paid to participants | 32676 |
| &nbsp;&nbsp;&nbsp;&nbsp;Administrative expenses | 215 |
| &nbsp;&nbsp;Total deductions | 32891 |
| Net increase before transfers | 5232 |
| &nbsp;&nbsp;Plan transfers (see Note 4) | 1240 |
| Net increase after transfers | 6472 |
| Net assets available for benefits: |  |
| &nbsp;&nbsp;Beginning of year | 149601 |
| &nbsp;&nbsp;**End of year** | $156073 |

---

See Notes to Financial Statements

------

[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Notes to Financial Statements**

**December 31, 2024 and 2023**

***(in thousands, except share amounts)***

#### Note 1. Description of Plan
The following description of the Mayville Engineering Company, Inc. 401(k) Plan (the Plan) provides only general information. Participants should refer to the Plan document for a more complete description of the Plan's provisions.

#### General
The Plan is a defined contribution plan covering substantially all employees of Mayville Engineering Company, Inc. (the Company). The Plan is intended to be a qualified retirement plan under the Internal Revenue Code (IRC) and the purpose is to enable eligible employees to save for retirement. The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974 (ERISA), as amended.

#### Eligibility
Employees become eligible to participate in the Plan for both employee and employer match contributions on the first entry date after an employee's hire date. The entry dates of the Plan are January 1, April 1, July 1 and October 1.

Employees are also eligible to receive Company profit sharing contributions after they have completed 1,000 hours of service within a plan year and are employed by the Company on the last day of the Plan year. There are certain circumstances where the eligibility rules are waived including military leave, medical leave, retirement and death.

#### Contributions
Each year, participants may contribute up to 50% of pretax annual compensation, as defined by the Plan. Participants may elect to have any portion, or all of their contributions designated as Roth 401(k) contributions. Participants who have attained age 50 before the end of the Plan year are eligible to make catch-up contributions. Participants may also contribute amounts representing distributions from other qualified defined benefit or defined contribution plans (rollover). Participants direct the investment of their contributions into various investment options offered by the Plan. The Plan includes an auto-enrollment provision whereby all newly eligible employees are automatically enrolled in the Plan unless they affirmatively elect not to participate in the Plan. Automatically enrolled participants have their deferral rate set at 4% of eligible compensation and their contributions invested in a designated balanced fund until changed by the participant. The Plan also has a provision for auto-escalation of contribution rates of 1% each year, capped at 6%.

All Plan participants are eligible for employer matching contributions equal to 50% of the participant's contributions up to a maximum of 6% of eligible compensation.

The Company can make a discretionary contribution of Company stock authorized by the Board of Directors. These Company discretionary contributions are usually approved at the end of each calendar year and funded in the subsequent year resulting in a contribution receivable on the Statements of Net Assets Available for Benefits. For a participant to be eligible for the Company discretionary contribution of Company stock, the participant must work 1,000 hours during the year and be employed at the end of the year. The Company did not make any discretionary contributions in the form of Company stock for the year ended December 31, 2024.

Contributions are subject to certain Internal Revenue Service (IRS) limitations.

#### Participant Accounts
Each participant's account is credited with the participant's contributions, Company's contributions and Plan earnings. Participant accounts are charged with an allocation of administrative expenses that are paid by the Plan. Allocations are based on participant earnings, account balances or specific participant transactions, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant's vested account balance.

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[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Notes to Financial Statements — (Continued)**

#### Vesting
Participants are immediately vested in their contributions and non-elective safe harbor contributions plus actual earnings thereon. Vesting in the Company's match and discretionary contribution portion of their accounts is based on years of continuous service. Participants are 100% vested in the Company's match and discretionary contributions after two years of credited service. Upon a participant's death or total disability, each participant's accrued benefits shall become 100% vested.

#### Notes Receivable from Participants
Participant loans are not permitted by the Plan.

#### Payment of Benefits
Active participants may elect a hardship distribution as eligible according to the Plan document under certain Plan and IRS conditions. On termination of service due to death, disability or retirement, a participant may elect to receive a lump sum amount equal to the value of the participant's vested interest in his or her account or periodic installments. For termination of service and for other reasons, a participant may receive the value of the vested interest in his or her account as a lump sum distribution. However, if the value of the vested benefit is less than $5, a lump sum distribution will be made regardless of whether or not an election has been made.

#### Forfeited Accounts
At December 31, 2024 and 2023, forfeited nonvested accounts totaled $48, and $153, respectively. These accounts can be used as, or offset, future Company contributions or cover administrative expenses. For the year ended December 31, 2024, Company contributions were reduced by $354 from forfeited nonvested accounts.

#### Administration
The Company is the administrator of the Plan and has appointed Principal Financial Group as recordkeeper, custodian and trustee. The custodian is responsible for investing and safekeeping all of the assets of the Plan.

#### Note 2. Summary of Significant Accounting Policies

#### Basis of Accounting
The Plan's financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (GAAP). Accordingly, the Plan's financial statements are prepared on the accrual basis of accounting.

#### Investment Valuation and Income Recognition
Investments are reported at fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. See Note 5 for further discussion on fair value measurements.

Purchases and sales of securities are recorded on a trade-date basis. Interest income is recorded on the accrual basis. Dividends are recorded on the ex-dividend date. Net appreciation includes the Plan's gains and losses on investments bought and sold, as well as, held during the year.

#### Use of Estimates
The preparation of financial statements in conformity with GAAP requires the Plan administrator to make estimates and assumptions that affect the reported amounts of the Plan's assets and liabilities and changes therein, and disclosure of contingent assets and liabilities. Actual results could differ from those estimates.

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[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Notes to Financial Statements — (Continued)**

#### Expenses
Administrative expenses may be paid either by the Plan or by the Company. Expenses paid by the Company are excluded from these financial statements. Certain expenses incurred in connection with the general administration of the Plan that are paid by the Plan are included in administrative expenses. In addition, certain investment related expenses are included in net appreciation in fair value of investments.

#### Payments of Benefits
Benefits are recorded when paid.

#### Subsequent Events
Subsequent events have been evaluated through the date the financial statements were available to be issued.

#### Note 3. Plan Termination
Although it has not expressed any intent to do so, the Company has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA. In the event of Plan termination, participants would become 100% vested in their Company contributions.

#### Note 4. Plan Transfers
Plan transfers for the year ended December 31, 2024 consists of:

---

| | |
|:---|:---|
|  | **2024** |
| ESOP diversification | $1240 |

---

***ESOP Diversification:*** Plan participants who also participate in the Mayville Engineering Company, Inc. Employee Stock Ownership Plan (ESOP) and meet certain eligibility requirements of that Plan are allowed to transfer a portion of their account balances from the ESOP to the 401(k) Plan under the diversification provisions of the ESOP Plan. Participants who have completed at least 10 years of service and have attained the age of 50 may elect to diversify their account balances and have the opportunity to transfer up to 25% of their ESOP balance into their Mayville Engineering Company, Inc. 401(k) Plan account during the next five-year period. After the five-year election period, additional transfers are allowed but are limited to 50% of their account balance.

In addition to the above, of the $4,679 of rollovers listed on the Statement of Changes in Net Assets Available for Benefits, $3,618 relate to rollover contributions from the Company's Employee Stock Ownership Plan.

#### Note 5. Fair Value Measurements
The framework for measuring fair value provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1) and the lowest priority to unobservable inputs (level 3). The three levels of the fair value hierarchy are described as follows:

Level 1 – Inputs to the valuation methodology are unadjusted quoted prices for identical assets or liabilities in active markets that the Plan has the ability to access.

Level 2 – Inputs to the valuation methodology include:

● quoted prices for similar assets or liabilities in active markets;

● quoted prices for identical or similar assets or liabilities in inactive markets;

● inputs other than quoted prices that are observable for the asset or liability;

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[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Notes to Financial Statements — (Continued)**

● inputs that are derived principally from or corroborated by observable market data by correlation or other means.

If the asset or liability has a specified (contractual) term, the Level 2 input must be observable for substantially the full term of the asset or liability.

Level 3 – Inputs to the valuation methodology are unobservable and significant to the fair value measurement.

The asset 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 relevant observable inputs and minimize the use of unobservable inputs.

The following is a description of the methodologies used for assets measured at fair value. There have been no changes in the methodologies used at December 31, 2024 and 2023.

Mutual Funds – Valued at the daily closing price as reported by the funds. 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 deemed to be actively traded.

Company Stock – Valued at the daily closing price as recorded by the New York Stock Exchange.

Collective Trust Fund – Valued at the NAV of units of a collective trust fund. The NAV, as provided by the Trustee, is used as a practical expedient to estimate the fair value. The NAV is based on the fair value of the underlying investments held by the fund less its liabilities. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Participant transactions (purchases and sales) may occur daily. There are no unfunded commitments within the Plan. Were the Plan to initiate a full redemption of the common collective trust, the investment advisor reserves the right to delay withdrawal from the trust for twelve months in order to ensure that securities liquidations will be carried out in an orderly manner.

The following table sets forth by level, within the fair value hierarchy, the Plan's assets at fair value as of December 31, 2024:

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **2024** | **2024** | **2024** | **2024** |
|  | **Level 1** | **Level 2** | **Level 3** | **Total** |
| Mutual funds | $122967 | $— | $— | $122967 |
| Company stock | 33106 |  |  | 33106 |
| Total investments at fair value |  |  |  | $156073 |

---

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[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Notes to Financial Statements — (Continued)**

The following table sets forth by level, within the fair value hierarchy, the Plan's assets at fair value as of December 31, 2023:

---

| | | | | |
|:---|:---|:---|:---|:---|
|  | **2023** | **2023** | **2023** | **2023** |
|  | **Level 1** | **Level 2** | **Level 3** | **Total** |
| Mutual funds | $95961 | $— | $— | $95961 |
| Company stock | 48075 |  |  | 48075 |
| Investments measured at NAV: |  |  |  |  |
| &nbsp;&nbsp;Collective trust fund\*\* |  |  |  | 5565 |
| Total investments at fair value |  |  |  | $149601 |

---

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\*\* Certain investments that were measured at net asset value per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the line items presented in the Statements of Net Assets Available for Benefits.

#### Note 6. Tax Status
The Company adopted a prototype volume submitter profit sharing 401(k) Plan with a cash or deferral arrangement which received a letter from the IRS dated June 30, 2020, stating that the Plan and related trust are designed in accordance with applicable sections of the IRC. The plan has been amended since receiving the opinion letter. The Plan Administrator believes that the Plan is designed, and is currently being operated, in compliance with the applicable requirements of the IRC and, therefore, believe that the Plan is qualified and the related trust is tax-exempt.

#### Note 7. Party-in-Interest and Related Party Transactions
Fees incurred by the Plan for investment management by Principal Financial Group, or its affiliates, are included in net appreciation in fair value of investments, as they are paid through revenue sharing, rather than a direct payment. Fees paid by the Plan for other administrative services amounted to $215 for the year ended December 31, 2024, which is included under administrative expenses on the Statement of Changes in Net Assets Available for Benefits.

The Plan also offers the Mayville Engineering Company (MEC) Stock Fund, which primarily consists of common stock as an investment option. The Company is the sponsoring employer and, therefore, a related party of the Plan. At December 31, 2024 and 2023, the Plan held 2,193,927 and 3,254,916 shares, respectively, of MEC common stock with a cost basis of $26,665 and $41,405, respectively. During 2024, the Plan acquired $4,337 of MEC Company stock. The Plan received proceeds from the sale of Company shares of $27,934 and realized a gain of $5,979 on these sales during 2024. The sales were participant directed transactions in 2024.

#### Note 8. Risks and Uncertainties
The Plan invests in various investment securities. Investment securities are exposed to various risks such as interest rate, market and credit risks. Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participants' account balances and the amounts reported in the Statements of Net Assets Available for Benefits.

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[**Table of Contents**](#TOC)

**Mayville Engineering Company, Inc.**

**401(k) Plan**

**Schedule H, Line 4i – Schedule of Assets (Held at End of Year)**

**December 31, 2024**

***(in thousands)***

**Plan Sponsor: Mayville Engineering Company, Inc.**

**Plan Sponsor EIN: 39-0944729**

**Plan Number: 003**

---

| | | | | |
|:---|:---|:---|:---|:---|
| <br>**(a)** | **(b)**<br>**Identity of Issue, Borrow,**<br>**Lessor, or Similar Party** | **(c)**<br>**Description of Investment Including Maturity Date, Rate**<br>**of Interest, Collateral, Par, or Maturity Value** | **(d)**<br>**Cost** | **(e)**<br>**Current Value** |
|  | &nbsp;&nbsp;Mutual Funds |  |  |  |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2030 | \*\* | $13037 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2035 | \*\* | 11560 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Fidelity | &nbsp;&nbsp;500 Index | \*\* | 11510 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2040 | \*\* | 10903 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Janus Henderson | &nbsp;&nbsp;Forty N | \*\* | 9600 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2025 | \*\* | 8414 |
| \* | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Principal Global Investors | &nbsp;&nbsp;Government Money Market R6 Fund | \*\* | 8015 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2045 | \*\* | 6989 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2050 | \*\* | 6759 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Janus Henderson | &nbsp;&nbsp;Research N | \*\* | 4498 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2055 | \*\* | 4298 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2060 | \*\* | 3270 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Nuveen | &nbsp;&nbsp;Small Cap Select | \*\* | 3087 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Fidelity | &nbsp;&nbsp;Advisor Stock Selector Mid Cap | \*\* | 2669 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;MFS | &nbsp;&nbsp;Value R3 | \*\* | 2473 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2020 | \*\* | 2338 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Capital Research and Mgmt. Co. | &nbsp;&nbsp;American Funds Capital World Growth and Income R6 | \*\* | 1989 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2065 | \*\* | 1982 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Capital Research and Mgmt. Co. | &nbsp;&nbsp;American Funds EuroPacific Growth R6 | \*\* | 1889 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;JPMorgan | &nbsp;&nbsp;Mid Cap Value R6 | \*\* | 1736 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;PIMCO | &nbsp;&nbsp;Total Return Institutional | \*\* | 1626 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement Balanced | \*\* | 1393 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Vanguard Group | &nbsp;&nbsp;Inflation-Protected Securities Admiral | \*\* | 1320 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Nuveen | &nbsp;&nbsp;Mid Cap Growth Opportunities | \*\* | 1109 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Nuveen | &nbsp;&nbsp;Real Estate Securities | \*\* | 294 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2010 | \*\* | 162 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;T. Rowe Price | &nbsp;&nbsp;Retirement 2015 | \*\* | 47 |
|  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total Mutual Funds |  |  | 122967 |
|  | &nbsp;&nbsp;Corporate Common Stock |  |  |  |
| \* | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;MEC | &nbsp;&nbsp;Common stock, no par value | \*\* | 33106 |
|  | &nbsp;&nbsp;Total |  |  | $156073 |

---

------

\* Represents a party-in-interest to the Plan.

\*\* Information not required for participant directed investments

See report of independent registered public accounting firm

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[**Table of Contents**](#TOC)

**Exhibit Index**

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| | | |
|:---|:---|:---|
| **Exhibit**<br>**Number** |  | **Description** |
| 23.1 |  | [Consent of Independent Registered Public Accounting Firm](tmb-20241231xex23d1.htm) |

---

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[**Table of Contents**](#TOC)

#### SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the trustees (or other persons who administer the employee benefit plan) have duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | | |
|:---|:---|:---|
|  | Mayville Engineering Company, Inc. 401(k) Plan | Mayville Engineering Company, Inc. 401(k) Plan |
| Date: June 20, 2025 | By: | /s/ Rachele M. Lehr |
|  |  | **Rachele M. Lehr** |
|  |  | **Chief Financial Officer** |

---

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## Exhibit 23.1

**EXHIBIT 23.1**

**CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM**

We consent to the incorporation by reference in the Registration Statement (No. 333-234505) on Form S-8 of Mayville Engineering Company, Inc. of our report dated June 20, 2025, with respect to the statements of net assets available for benefits of the Mayville Engineering Company, Inc. 401(k) Plan as of December 31, 2024 and 2023, the related statement of changes in net assets available for benefits for the year ended December 31, 2024, and the related supplemental schedule as of December 31, 2024, which report appears in the December 31, 2024 annual report on Form 11-K of the Mayville Engineering Company, Inc. 401(k) Plan.

/s/ Wipfli LLP

Minneapolis, Minnesota

June 20, 2025

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