Material Event (Form 8-K)

On May 7, 2026, LifeStance Health Group, Inc. (the "Company") entered into an Underwriting Agreement (the "Underwriting Agreement") by and among the Company, J.P. Morgan Securities LLC (the "Underwriter"), and the selling stockholders named in Schedule II thereto (the "Selling Stockholders"), relating to the underwritten offering of 35,000,000 shares (the "Shares") of the Company's common stock, par value $0.01 per share (the "Common Stock"), pursuant to the Company's registration statement on Form S-3 (File No. 333-279585), filed on May 21, 2024 (the "Registration Statement"). In addition, pursuant to the Underwriting Agreement, the Company has agreed to purchase from the Underwriter 6,000,000 Shares sold by the Selling Stockholders to the Underwriter, at a price per share equal to the price per share paid by the Underwriter to the Selling Stockholders. The Underwriter did not receive any compensation for shares of the Common Stock being repurchased by the Company.

All of the Shares are being sold by the Selling Stockholders. The Company did not receive any proceeds from the offering. The closing of the offering occurred on May 12, 2026. 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.

Ropes & Gray LLP, counsel to the Company, has issued an opinion to the Company regarding the Shares sold in the offering. A copy of the opinion is filed as Exhibit 5.1 to this Current Report on Form 8-K.