Regulation FD Disclosure (Form 8-K)

Members of the senior management team of Acadia Healthcare Company, Inc. (the "Company") are scheduled to participate in a fireside chat at the Jefferies 2025 Healthcare Services Conference on September 29, 2025. In conjunction with this fireside chat, the Company today is announcing preliminary guidance for 2026 with respect to expected total capital expenditures and bed growth. Total capital expenditures are expected to decline at least $300 million relative to 2025 guidance of $600 to $650 million, as provided in its press release that was previously furnished as Exhibit 99 to the Company's Current Report on Form 8-Kfiled with the Securities and Exchange Commission (the "SEC") on August 5, 2025. The Company also expects to add 500 to 700 beds in 2026, inclusive of beds currently under construction in 2025.

The Company is also providing a select interim operating result for the third quarter of 2025, announcing same facility patient days growth to date of approximately 1.3%. For an explanation of how same facility results are calculated and the Company's rationale for presenting them to investors, please see Item 2. "Management's Discussion and Analysis of Financial Condition and Results of Operations" in the Company's Quarterly Report on Form 10-Qfor the quarterly period ended June 30, 2025, filed with the SEC on August 5, 2025.

The information furnished pursuant to Item 7.01 in this Current Report on Form 8-Kis being furnished and shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended (the "Securities Act"), or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.