COMFORT SYSTEMS USA INC — Director's Dealing 2021

May 25, 2021

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: COMFORT SYSTEMS USA INC (FIX)
CIK: 0001035983
Period of Report: 2021-05-24

Reporting Person: Trent T McKenna (Chief Operating Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2021-05-24	Common Stock	M	3000	$30.36	Acquired	33017	Direct
2021-05-24	Common Stock	M	3000	$36.25	Acquired	36017	Direct
2021-05-24	Common Stock	M	3000	$42.50	Acquired	39017	Direct
2021-05-24	Common Stock	S	9000	$80.6952	Disposed	30017	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2021-05-24	Option to Buy	$30.36	M	3000	Disposed	2026-03-23	Common Stock (3000)	Direct
2021-05-24	Option to Buy	$36.25	M	3000	Disposed	2027-03-08	Common Stock (3000)	Direct
2021-05-24	Option to Buy	$42.50	M	3000	Disposed	2028-03-07	Common Stock (3000)	Direct

Footnotes

F1: Represents the average price of shares sold; full information regarding the number of shares sold and specific prices will be made available upon request to the Company's Office of the General Counsel.

F2: Stock options were granted on 03/23/2016, vested equally over a three-year period, and were fully vested on 04/01/2019.

F3: Stock options were granted on 03/08/2017, vested equally over a three-year period, and were fully vested on 04/01/2020.

F4: Stock options were granted on 03/07/2018, vested equally over a three-year period, and were fully vested on 04/01/2021.