8-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): April 17, 2026

Avantor, Inc.

(Exact name of registrant as specified in its charter)

Delaware	001-38912	82-2758923
(State or other jurisdiction of incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

Radnor Corporate Center, Building One, Suite 200

100 Matsonford Road

Radnor, Pennsylvania 19087

(Address of principal executive offices, including zip code)

(610) 386-1700

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

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:

Title of each class	Trading Symbol	Exchange on which registered
Common Stock, $0.01 par value	AVTR	New York Stock Exchange

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. ☐

Item 5.02.    Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On April 23, 2026, Avantor, Inc. (the “Company”) filed a Current Report on Form 8-K (the “Original 8-K”) disclosing that Benoit Gourdier, the Company’s Executive Vice President, Bioscience and Medtech Products, would transition to a new role supporting the Company’s segment integration activities for a period of time, after which he would depart the Company. The Original 8-K did not include Mr. Gourdier’s departure date because, at the time, his departure date had not been determined. This Form 8-K/A is being filed for the purpose of providing Mr. Gourdier’s departure date.

On August 21, 2026, the Company, through its subsidiary VWR International, LLC, and Mr. Gourdier agreed to a transition arrangement (the “Transition Agreement”), pursuant to which Mr. Gourdier will continue his employment with the Company through October 14, 2026, after which his employment will end. If Mr. Gourdier remains employed and complies with the terms of the Transition Agreement until October 14, 2026, he will be entitled to receive severance benefits materially consistent with the terms of the Company’s Executive Severance and Change in Control Plan, which are described in the Company’s proxy statement filed with the Securities and Exchange Commission on March 27, 2026.

Item 9.01.    Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.	Description
104	The cover page from this Current Report on Form 8-K/A, formatted in Inline XBRL

SIGNATURE

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.

	Avantor, Inc.
Date: August 27, 2026	By:	/s/ Claudius Sokenu
		Name:	Claudius Sokenu
		Title:	Executive Vice President, Chief Legal and Compliance Officer and Secretary (Duly Authorized Officer)

XML

Document and entity information	Apr. 17, 2026
Document Information [Line Items]
Document Type	8-K/A
Amendment Flag	false
Document Period End Date	Apr. 17, 2026
Entity Central Index Key	0001722482
Entity Registrant Name	Avantor, Inc.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-38912
Entity Tax Identification Number	82-2758923
Entity Address, Address Line One	Radnor Corporate Center, Building One, Suite 200
Entity Address, Address Line Two	100 Matsonford Road
Entity Address, City or Town	Radnor
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19087
City Area Code	(610)
Local Phone Number	386-1700
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Common Stock
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	AVTR
Security Exchange Name	NYSE