LETTER AGREEMENT

Amended and Restated Distribution Agreement

July 1, 2021

AMG Distributors, Inc.

One Stamford Plaza

263 Tresser Boulevard, Suite 949

Stamford, CT 06901

Attn: Keitha L. Kinne, Chief Operating Officer

Ladies and Gentlemen:

AMG Funds III (the “Trust”) hereby notifies you that it desires (i) to amend and restate Appendix A to the Distribution Agreement and (ii) to delete Section 16 of the Distribution Agreement. Attached as Exhibit A is an amended and restated Appendix A to the Distribution Agreement.

Please acknowledge your agreement to amend and restate Appendix A to the Distribution Agreement and to delete Section 16 of the Distribution Agreement by executing this letter agreement in the space provided below and then returning it to the undersigned.

Sincerely,

AMG Funds III

ACKNOWLEDGED AND ACCEPTED

AMG Distributors, Inc.

Exhibit A

AMENDED AND RESTATED APPENDIX A

AMG GW&K ESG Bond Fund

AMG GW&K International Small Cap Fund

AMG GW&K High Income Fund

AMG Veritas Asia Pacific Fund

Date: July 1, 2021

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in this Registration Statement on Form N-1A of our report dated July 21, 2021, relating to the financial statements and financial highlights, which appears in the Annual Report on Form N-CSR for the year ended May 31, 2021 of AMG GW&K International Small Cap Fund. We also consent to the references to us under the headings “Disclosure of Portfolio Holdings”, “Financial Statements”, “Independent Registered Public Accounting Firm” and “Financial Highlights” in such Registration Statement.

/s/ PricewaterhouseCoopers LLP

Boston, Massachusetts

September 28, 2021

AMG FUNDS

AMG FUNDS I

AMG FUNDS II

AMG FUNDS III

AMG FUNDS IV

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that, effective as of September 17, 2021, the person whose name appears below hereby nominates, constitutes and appoints Keitha L. Kinne, Thomas Disbrow and Mark J. Duggan (with full power to each of them to act alone) his true and lawful attorney-in-fact and agent, for him and on his behalf and in his place and stead in any way and all capacities, to make, execute and sign any and all Registration Statements on Form N-1A, any other registration statement and any pre- and post-effective amendments and supplements thereto under the Securities Act of 1933, as amended, and/or the Investment Company Act of 1940, as amended, of AMG Funds, AMG Funds I, AMG Funds II, AMG Funds III and AMG Funds IV (the “Trusts”), and to file the same with the Securities and Exchange Commission, and any other regulatory authority having jurisdiction over the offer and sale of shares of beneficial interest of the Trusts, and any and all exhibits and other documents requisite in connection therewith, granting unto said attorneys and each of them, full power and authority to perform each and every act and thing requisite and necessary to be done in and about the premises as fully to all intents and purposes as the undersigned himself might or could do.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand as of the date written below.

AMG FUNDS III

AMENDED AND RESTATED MULTIPLE CLASS EXPENSE

ALLOCATION PLAN PURSUANT TO RULE 18f-3

As of June 11, 2021

AMG Funds III, a Massachusetts business trust (the “Trust”), engages in business as an open-end management investment company. The Trust issues shares of beneficial interest in separate series, with shares of each series representing interests in a separate portfolio of securities and other assets (the Trust’s series together with all other such series subsequently established by the Trust are referred to herein individually as a “Series” and, collectively, as the “Series”). The Trust has designated for certain Series certain separate classes of shares, as set forth on Schedule B hereto (each a “Class” and collectively, the “Classes”). A majority of the Trustees of the Trust, including a majority of the Trustees who are not interested persons of the Trust (as defined in the Investment Company Act of 1940, as amended (“1940 Act”) (“Independent Trustees”)), having been furnished with and having evaluated information reasonably necessary to evaluate this Amended and Restated Multiple Class Expense Allocation Plan Pursuant to Rule 18f-3 (“Plan”), have determined in the exercise of their reasonable business judgment that the Plan, including the expense allocation provisions thereof, is in the best interests of each Class of each Series individually, and each Series and the Trust as a whole. In making its determination, the Trust’s Board of Trustees (the “Board”) focused on, among other things, the relationship between or among the Classes and examined possible conflicts of interest among Classes (including those potentially involving cross-subsidization between Classes) regarding the allocation of expenses, fees, waivers and expense reimbursements. The Trustees also evaluated the level of services provided to each Class and the cost of those services in order to ensure that the services were appropriate and the allocation of expenses was reasonable. Accordingly, the Trust has hereby adopted this Plan on behalf of its Series set forth on Schedule A hereto, as amended from time to time.

Section 1. Class Differences.

Each Class of a Series shall represent an equal pro rata interest in the same portfolio of investments of that Series and, except as otherwise set forth in this Plan, shall differ solely with respect to: (i) distribution, service and other charges and expenses as provided for in Sections 2 and 3 of this Plan; (ii) the exclusive voting rights of each Class on matters submitted to shareholders that relate solely to that Class; (iii) the separate voting rights of each Class on matters submitted to shareholders in which the interests of one Class differ from the interests of another Class; (iv) such differences relating to eligible investors as may be set forth in the prospectuses and statements of additional information of each Series, as the same may be amended or supplemented from time to time (each a “Prospectus” and “SAI” and collectively, the “Prospectus” and “SAI”); (v) the designation of each Class; and (vi) exchange privileges as provided for in Section 4.

Section 2. Distribution and Service Arrangements.

Class N shares shall be offered without imposition of an initial sales charge or contingent deferred sales charge. Class N shares of certain Series shall be charged annual distribution and service fees under a Plan of Distribution Adopted Pursuant to Rule 12b-1 under the 1940 Act (the “Rule 12b-1 Plan”). The amount of distribution and shareholder servicing fees under the Rule 12b-1 Plan (“Rule 12b-1 Plan Fees”) pertaining to the Class N shares of the applicable Series are set forth on Schedule B hereto. Class N shares shall be sold only to those investors meeting the eligibility requirements set forth in the Prospectus and SAI. Class N shares also may pay fees for shareholder servicing provided by financial intermediaries (“Financial Intermediary Shareholder Servicing Fees”) as set forth on Schedule B hereto.

Class I shares shall be offered without imposition of an initial sales charge or contingent deferred sales charge and are not subject to any Rule 12b-1 Plan Fees. Class I shares shall be sold only to those investors meeting the eligibility requirements set forth in the Prospectus and SAI. Class I shares for certain Series also may pay Financial Intermediary Shareholder Servicing Fees as set forth on Schedule B hereto.

Class Z shares shall be offered without imposition of an initial sales charge or contingent deferred sales charge and are not subject to any Rule 12b-1 Plan Fees. Class Z shares shall be sold only to those investors meeting the eligibility requirements set forth in the Prospectus and SAI.

Section 3. Expense Allocation.

(a) Class Expenses.

Certain expenses may be attributable to a particular Class (“Class Expenses”). Class Expenses shall be allocated exclusively to the particular Class to which they are attributable. A Class may pay a different share of other expenses, not including advisory or custodial fees or other expenses related to the management of the Series’ assets, if (i) such expenses are actually incurred in a different amount by that Class, or if the Class receives services of a different kind or to a different degree than other Classes and (ii) the Board has approved such allocation. In addition to Rule 12b-1 Plan Fees and Financial Intermediary Shareholder Servicing Fees described in Section 2 above, Class Expenses may include (a) expenses associated with the addition of classes of shares to the Trust (to the extent that the expenses were not fully accrued prior to the issuance of the new classes of shares); (b) expenses of administrative personnel and services required to support the shareholders of a specific Class; (c) litigation or other legal expenses relating to a specific Class of shares; (d) Trustees’ fees or expenses incurred as a result of issues relating to a specific Class of shares, (e) accounting expenses relating to a specific Class of shares; (f) transfer agency fees and

expenses; and (g) other expenses, not including advisory or custodial fees or other expenses related to the management of the Series’ assets, if such expenses are actually incurred in a different amount by a specific Class of shares, or if the Class receives services of a different kind or to a different degree than other Classes.

Expenses attributable to a Series other than Class Expenses shall be allocated to each Class pro rata based on its net asset value relative to the net asset value of the Series. Notwithstanding the foregoing, the underwriter, investment advisor, subadvisor or other provider of services to a Series may waive or reimburse the expenses of a specific Class or Classes of the Series to the extent permitted under Rule 18f-3 under the 1940 Act; provided, however, that the Board shall monitor the use of waivers or expense reimbursements intended to differ by Class.

Section 4. Exchange Privilege.

Shares of a Class may be exchanged by a shareholder for shares of another Series or for shares of certain other series advised by AMG Funds LLC, as set forth in the Prospectus. Shares of a Class also may be exchanged for shares of a third-party money market fund, as described in the Prospectus.

Section 5. Additional Information.

The Prospectus and SAI contain additional information about each Class and the Series’ multiple class structure. This Plan is subject to the terms of the Prospectus and SAI; provided, however, that none of the terms set forth in the Prospectus and SAI shall be inconsistent with the terms of this Plan.

Section 6. Term and Termination.

(a) The Series.

This Plan shall become effective with respect to each Series as set forth on Schedule A hereto, and shall continue in effect with respect to the Classes of each such Series until terminated in accordance with the provisions of Section 6(b) hereof.

(b) Termination.

This Plan may be terminated at any time with respect to the Trust or any Series or Class thereof, as the case may be, by vote of a majority of both the Trustees of the Trust and the Independent Trustees. The Plan may remain in effect with respect to the Trust or any Series or Class thereof even if it has been terminated in accordance with this Section 6(b) with respect to any other Series or Class of the Trust.

Section 7. Amendments.

Before any material amendment to this Plan affecting the Trust or any Series or Class thereof, a majority of both the Trustees of the Trust and the Independent Trustees shall find that the amendment, including the expense allocation, is in the best interests of each Class of each Series individually and each Series and the Trust as a whole.

Amended and Restated as of June 11, 2021

AMG FUNDS III

MULTIPLE CLASS EXPENSE ALLOCATION PLAN

PURSUANT TO RULE 18f-3

SCHEDULE A

Series

AMG GW&K ESG Bond Fund

AMG GW&K High Income Fund

AMG GW&K International Small Cap Fund

AMG Veritas Asia Pacific Fund

AMG FUNDS III

MULTIPLE CLASS EXPENSE ALLOCATION PLAN

PURSUANT TO RULE 18f-3

SCHEDULE B

AMG GW&K ESG Bond Fund

AMG GW&K High Income Fund

AMG GW&K International Small Cap Fund

AMG Veritas Asia Pacific Fund