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) August 11, 2016

Comfort Systems USA, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (713) 830-9600

(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:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01              Other Events

Attached and incorporated herein by reference as Exhibit 99.1 is a copy of a press release of Comfort Systems USA, Inc. (the “Company”) dated August 16, 2016 announcing that the Company’s Board of Directors has approved an amendment to the Company’s stock repurchase program to increase the shares authorized and remaining as available to purchase back up to 1,000,000 shares by authorizing the company to acquire up to 551,310 additional shares of its outstanding common stock.  The Company’s existing stock repurchase program had previously authorized the repurchase of up to 7,561,183 shares of the company’s outstanding common stock.

Through August 11, 2016, the Company repurchased 7,112,493 shares of the Company’s common stock at an aggregate price of $89,204,333.  This extension of the stock repurchase program will “top off” the plan and permit the Company to repurchase up to an additional 1,000,000 shares of its currently outstanding common stock beyond what had already been purchased as of August 11, 2016.

The share repurchases will be made from time to time at the Company’s discretion in the open market or privately negotiated transactions as permitted by securities laws and other legal requirements, and subject to market conditions and other factors.  The Company expects that the share repurchases will be financed with available cash.  The Company’s Board of Directors may modify, suspend, extend or terminate the program at any time.

ITEM 9.01           Financial Statements and Exhibits

The following Exhibits are included herein:

Exhibit 99.1 Press Release of Comfort Systems USA, Inc. dated August 16, 2016 announcing that the Company’s Board of Directors has approved an amended stock repurchase program.

2

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.

3

EXHIBIT INDEX

4

Exhibit 99.1

FOR IMMEDIATE RELEASE

COMFORT SYSTEMS USA INCREASES STOCK REPURCHASE PROGRAM

Houston, TX — August 16, 2016 — Comfort Systems USA, Inc. (NYSE: FIX), a leading provider of commercial, industrial and institutional heating, ventilation and air conditioning (“HVAC”) services, today announced that its board of directors has approved an amendment to the Company’s stock repurchase program to increase the shares authorized and remaining as available to purchase back up to 1,000,000 shares by authorizing the Company to acquire up to 551,310 additional shares of its outstanding common stock. The Company’s existing stock repurchase program had previously authorized the repurchase of up to 7,561,183 shares of the Company’s outstanding common stock.

Through August 11, 2016, the Company repurchased 7,112,493 shares of the Company’s common stock at an aggregate price of $89,204,333. This extension of the stock repurchase program will “top off” the plan and permit the Company to repurchase up to an additional 1,000,000 shares of its currently outstanding common stock beyond what had already been purchased as of August 11, 2016.

The share repurchases will be made from time to time at the Company’s discretion in the open market or privately negotiated transactions as permitted by securities laws and other legal requirements, and subject to market conditions and other factors. The Company expects that the share repurchases will be financed with available cash. The Company’s board of directors may modify, suspend, extend, or terminate the program at any time.

Comfort Systems USA® is a premier provider of business solutions addressing workplace comfort, with 91 locations in 84 cities around the nation.  For more information, visit the Company’s website at www.comfortsystemsusa.com.

Certain statements and information in this press release may constitute forward-looking statements regarding our future business expectations, which are subject to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. The words “believe,” “expect,” “anticipate,” “plan,” “intend,” “foresee,” “should,” “would,” “could,” or other similar expressions are intended to identify forward-looking statements, which are generally not historic in nature. These forward-looking statements are based on the current expectations and beliefs of Comfort Systems USA, Inc. and its subsidiaries (collectively, the “Company”) concerning future developments and their effect on the Company. While the Company’s management believes that these forward-looking statements are reasonable as and when made, there can be no assurance that future developments affecting the Company will be those that it anticipates. All comments concerning the Company’s expectations for future revenue and operating results are based on the Company’s forecasts for its existing operations and do not include the potential

impact of any future acquisitions. The Company’s forward-looking statements involve significant risks and uncertainties (some of which are beyond the Company’s control) and assumptions that could cause actual future results to differ materially from the Company’s historical experience and its present expectations or projections. Important factors that could cause actual results to differ materially from those in the forward-looking statements include, but are not limited to: the use of incorrect estimates for bidding a fixed-price contract; undertaking contractual commitments that exceed the Company’s labor resources; failing to perform contractual obligations efficiently enough to maintain profitability; national or regional weakness in construction activity and economic conditions; financial difficulties affecting projects, vendors, customers, or subcontractors; the Company’s backlog failing to translate into actual revenue or profits; failure of third party subcontractors and suppliers to complete work as anticipated;  difficulty in obtaining or increased costs associated with bonding and insurance; impairment to goodwill; errors in the Company’s percentage-of-completion method of accounting; the result of competition in the Company’s markets; the Company’s decentralized management structure; material failure to comply with varying state and local laws, regulations or requirements; debarment from bidding on or performing government contracts; shortages of labor and specialty building materials; retention of key management; seasonal fluctuations in the demand for mechanical systems; the imposition of past and future liability from environmental, safety, and health regulations including the inherent risk associated with self-insurance; adverse litigation results; an increase in our effective tax rate; an information technology failure or cyber security breach; and other risks detailed in our reports filed with the Securities and Exchange Commission.

For additional information regarding known material factors that could cause the Company’s results to differ from its projected results, please see its filings with the SEC, including its Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K.

Readers are cautioned not to place undue reliance on forward-looking statements, which speak only as of the date hereof. The Company undertakes no obligation to publicly update or revise any forward-looking statements after the date they are made, whether as a result of new information, future events, or otherwise.