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): November 5, 2020

Avantor, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (610) 386-1700

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:

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 November 5, 2020, Avantor, Inc. (the “Company”) entered into an Underwriting Agreement (the “Underwriting Agreement”), by and among the Company, the selling stockholders named therein (collectively, the “Selling Stockholders”), and Goldman Sachs & Co. LLC and J.P. Morgan Securities LLC, as representatives of the several underwriters named therein (the “Underwriters”), relating to an underwritten offering of 71,569,765 shares (the “Offered Shares”) of the Company’s common stock, par value $0.01 per share (“Common Stock”), pursuant to the Company’s Registration Statement on Form S-3 (File No. 333-248127), filed on August 19, 2020. The Selling Stockholders also granted the Underwriters a 30-day option to purchase up to 7,156,975 additional shares of Common Stock (the “Option Shares” and, together with the Offered Shares, the “Shares”), which was exercised in full. Pursuant to the Underwriting Agreement, the Selling Stockholders sold the shares for gross proceeds of approximately $1,988 million. The Company did not receive any proceeds from the offering. The offering of the Shares was completed on November 10, 2020.

The description of the Underwriting Agreement is qualified in its entirety by the terms of such agreement, which is incorporated herein by reference and attached to this report as Exhibit 1.1.

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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.