Form DSTRBRPT/A INTER-AMERICAN DEVELOPME

File No. 83-1

Regulation IA

Rule 3

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

100 F Street, NE

Washington, D.C. 20549

AMENDED REPORT OF

THE INTER-AMERICAN DEVELOPMENT BANK

(the “Bank”)

In respect of the Bank’s

Series No. 1039, Tranche No. 02

U.S.$150,000,000 Floating Rate Notes due February 18, 2031, as from April 28, 2026 to be consolidated and form a single series with the Bank’s U.S.$750,000,000 Floating Rate Notes due February 18, 2031 issued on February 18, 2026 (Series No. 1039, Tranche No. 01)

Filed pursuant to Rule 3 of Regulation IA

Dated: April 29, 2026

File No. 83-1

Regulation IA

Rule 3

This Amended Report to amend the current Report on Form DSTRBRPT filed by the Bank on April 28, 2026 (the “Original DSTRBRPT”), is filed to amend the Terms Agreement (Exhibit C to the Original DSTRBRPT) to modify Section 2 therein, and to file a copy of the amended Terms Agreement, attached to this Amended Report as Exhibit C.

Exhibit C

EXECUTION VERSION

TERMS AGREEMENT NO. 1039 TRANCHE 2 UNDER

THE PROGRAM

April 24, 2026

Inter-American Development Bank

1300 New York Avenue, N.W.

Washington, D.C. 20577

The undersigned agrees to purchase from you (the “Bank”) the Bank’s USD150,000,000 Floating Rate Notes due February 18, 2031 (the “Notes” as from April 28, 2026 to be consolidated and form a single series with the Bank’s USD750,000,000 Floating Rate Notes due February 18, 2031, issued on February 18, 2026 (Tranche 1)) described in the Pricing Supplement related thereto, dated as of the date hereof (the “Pricing Supplement”), at 9:00 a.m. New York time on April 28, 2026 (the “Settlement Date”), at an aggregate purchase price of USD151,200,000, calculated as set forth below, on the terms set forth herein and in the Standard Provisions, dated as of June 1, 2021, relating to the issuance of Notes by the Bank (the “Standard Provisions”), incorporated herein by reference. In so purchasing the Notes, the undersigned understands and agrees that it is not acting as an agent of the Bank in the sale of the Notes.

When used herein and in the Standard Provisions as so incorporated, the term “Notes” refers to the Notes as defined herein and the term “Time of Sale” refers to April 21, 2026, 12:18 p.m. New York time. The Uniform Fiscal Agency Agreement, dated as of July 20, 2006, as amended and supplemented from time to time, between the Bank and the Federal Reserve Bank of New York, as fiscal and paying agent, has been superseded by the Uniform Fiscal Agency Agreement, dated as of December 19, 2024 (the “New Fiscal Agency Agreement”), as may be amended, restated, superseded or otherwise modified from time to time, between the Bank and the 12 Federal Reserve Banks. When used herein and in the Standard Provisions as so incorporated, the term “Fed Fiscal Agency Agreement” refers to the New Fiscal Agency Agreement. All other terms defined in the Prospectus, the Pricing Supplement relating to the Notes and the Standard Provisions shall have the same meaning when used herein.

The Bank represents and warrants to us that the representations, warranties and agreements of the Bank set forth in Section 2 of the Standard Provisions (with the “Prospectus” revised to read the “Prospectus as amended and supplemented with respect to Notes at the date hereof”) are true and correct on the date hereof.

The obligation of the undersigned to purchase Notes hereunder is subject to the continued accuracy, on each date from the date hereof to and including the Settlement Date, of the Bank’s representations and warranties contained in the Standard Provisions and to the Bank’s performance and observance of all applicable covenants and agreements contained therein. The obligation of the undersigned to purchase Notes hereunder is further subject to the receipt by the undersigned of the documents referred to in Section 6(b) of the Standard Provisions.

Subject to Section 5(f) of the Standard Provisions, the Bank certifies to the undersigned that, as of the Settlement Date, (i) the representations and warranties of the Bank contained in the Standard Provisions are true and correct as though made at and as of the Settlement Date, (ii) the Bank has performed all of its obligations under this Terms Agreement required to be performed or satisfied on or prior to the Settlement Date, and (iii) the Prospectus contains all material information relating to the assets and liabilities, financial position, and net income of the Bank, and nothing has happened or is expected to happen which would require the Prospectus to be supplemented or updated.

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For purposes hereof, the notice details of the undersigned are as follows:

FOR THE BANK:

Inter-American Development Bank

1300 New York Avenue, N.W.

Washington, D.C. 20577

Attention:  Finance Department,

     Cash Management and Settlements Group

Email:    [email protected]

Telephone: 202-623-3131

FOR THE DEALER:

Banco Santander, S.A.

Ciudad Grupo Santander

Avenida de Cantabria s/n

Edificio Encinar

28660 Boadilla del Monte

Madrid, Spain

Attention:  Head of Debt Capital Markets

Email:   [email protected]

Telephone:  +34 912572029

(i) Acknowledges that: (A) under the provisions of Section 11(a) of the Inter-American Development Bank Act, the Notes are exempted securities within the meaning of Section 3(a)(2) of the U.S. Securities Act of 1933, as amended, and Section 3(a)(12) of

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the U.S. Securities Exchange Act of 1934, as amended, and (B) no action has been or will be taken by the Bank that would permit a public offering of the Notes, or possession or distribution of any offering material relating to the Notes in any jurisdiction where action for that purpose is required. Accordingly, the undersigned agrees that it will observe all applicable provisions of law in each jurisdiction in or from which it may offer or sell Notes or distribute any offering material.

(ii) Represents and agrees that (a) it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the Financial Services and Markets Act 2000 (the “FSMA”)) received by it in connection with the issue or sale of the Notes in circumstances in which Section 21(1) of the FSMA does not apply to the Bank, and (b) it has complied and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to such Notes in, from or otherwise involving the United Kingdom.

(iii) Represents, warrants and agrees that it has not offered or sold any Notes or caused the Notes to be made the subject of an invitation for subscription or purchase and will not offer or sell any Notes or cause the Notes to be made the subject of an invitation for subscription or purchase, and has not circulated or distributed, nor will it circulate or distribute the Prospectus, the Pricing Supplement or any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the Notes, whether directly or indirectly, to any person in Singapore other than: (i) to an institutional investor (as defined in Section 4A of the SFA) pursuant to Section 274 of the SFA or (ii) to an accredited investor (as defined in Section 4A of the SFA) pursuant to and in accordance with the conditions specified in Section 275 of the SFA and (where applicable) Regulation 3 of the Securities and Futures (Classes of Investors) Regulations 2018 of Singapore. Any reference to the SFA in this Terms Agreement is a reference to the Securities and Futures Act 2001 of Singapore and a reference to any term that is defined in the SFA or any provision in the SFA is a reference to that term or provision as amended or modified from time to time including by such of its subsidiary legislation as may be applicable at the relevant time.

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(iv) Acknowledges that: In the case of the Notes being offered into Singapore in a primary or subsequent distribution, and solely for the purposes of its obligations pursuant to Section 309B of the SFA, the Issuer has determined, and hereby notifies all relevant persons (as defined in Section 309A of the SFA) that the Notes are “prescribed capital markets products” (as defined in the Securities and Futures (Capital Markets Products) Regulations 2018 of Singapore) and Excluded Investment Products (as defined in MAS Notice SFA 04-N12: Notice on the Sale of Investment Products and MAS Notice FAA-N16: Notice on Recommendations on Investment Products).

Solely for the purposes of the requirements of Article 9(8) of the MiFID Product Governance rules under EU Delegated Directive 2017/593 (the “MiFID Product Governance Rules”) regarding the mutual responsibilities of manufacturers under the MiFID Product Governance Rules, the Dealer acknowledges that it understands the responsibilities conferred upon it under the MiFID Product Governance Rules relating to each of the product approval process, the target market and the proposed distribution channels as applying to the Notes and the related information set out in the Pricing Supplement and any other announcements in connection with the Notes.

Solely for the purposes of the requirements of 3.2.7R of the FCA Handbook Product Intervention and Product Governance Sourcebook (the “UK MiFIR Product Governance Rules”) regarding the mutual responsibilities of manufacturers under the UK MiFIR Product Governance Rules, the Dealer acknowledges that it understands the responsibilities conferred upon it under the UK MiFIR Product Governance Rules relating to each of the product approval process, the target market and the proposed distribution channels as applying to the Notes and the related information set out in the Pricing Supplement and any other announcements in connection with the Notes.

For the purposes of this provision, the expression “MiFID II” means Directive 2014/65/EU, as amended, and the expression “UK MiFIR” means Regulation (EU) No 600/2014 as it forms part of United Kingdom domestic law by virtue of the European Union (Withdrawal) Act 2018, as amended.

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For the avoidance of doubt, nothing in this Terms Agreement or any other agreements, arrangements, or understanding between the undersigned and the Bank shall operate as or be construed to constitute a waiver, renunciation or any other modification of any privilege or immunity of the Bank or its employees under the Agreement Establishing the Inter-American Development Bank, international law or other applicable law.

All notices and other communications hereunder shall be in writing and shall be transmitted in accordance with Section 10 of the Standard Provisions.

This Terms Agreement shall be governed by and construed in accordance with the laws of the State of New York.

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This Terms Agreement may be executed by any one or more of the parties hereto in any number of counterparts, each of which shall be deemed to be an original, but all such respective counterparts together shall constitute one and the same instrument.