UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF

THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported)  June 11, 2025

AMPHENOL CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (203) 265-8900

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

On June 11, 2025, Amphenol Corporation (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) by and between the Company and BNP PARIBAS, Citigroup Global Markets Limited, Commerzbank Aktiengesellschaft, Barclays Bank PLC, HSBC Bank plc, Mizuho International plc, The Toronto-Dominion Bank, Goldman Sachs & Co. LLC, J.P. Morgan Securities plc, ING Bank N.V. Belgian Branch, Siebert Williams Shank & Co., LLC, Standard Chartered Bank and U.S. Bancorp Investments, Inc., relating to the offer and sale of €600,000,000 aggregate principal amount of the Company’s 3.125% Senior Notes due 2032 (the “Euro Notes”).

The closing of the Euro Notes offering is expected to occur on June 16, 2025, subject to the satisfaction of customary closing conditions.

A copy of the Underwriting Agreement is attached hereto as Exhibit 1.1 and is filed herewith for purposes of incorporation by reference into the Company’s Registration Statement (No. 333-270605).

The above description of the Underwriting Agreement is qualified in its entirety by reference to the Underwriting Agreement, a copy of which is attached as Exhibit 1.1 to this Current Report on Form 8-K and is incorporated by reference herein.

On June 11, 2025, the Company issued a press release announcing the pricing of the Euro Notes, which is attached hereto as Exhibit 99.1 and is incorporated by reference herein.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.