Comfort Systems USA adds $3.8bn of backlog in a quarter, and labour is the limit

Comfort Systems USA reported its third-quarter 2026 results on 22 October. The Houston-based HVAC, mechanical and electrical contractor posted revenue of $3.77bn for the three months to 30 September, against $2.45bn in the same quarter of 2025, and net income of $489.0m, up from $291.6m.

The backlog

The headline number is backlog. Comfort Systems closed the quarter with $17.81bn of contracted work, up from $14.06bn at the end of June and $9.38bn a year earlier. Same-store backlog, which strips out acquisitions, was $17.39bn. CEO Brian Lane put it down to demand: "Relentless demand, together with our competence and reputation, produced sequential backlog growth of $3.8 billion."

Cash followed the bookings. Operating cash flow passed $1bn in the quarter for the first time, at $1.01bn, while gross margin held at 24.8%, the same as a year ago. Diluted earnings per share came in at $13.91, compared with $8.25.

What the market made of it

The quarter beat expectations. StockStory put the consensus at $3.40bn of revenue and $12.71 of earnings per share. Even so, the shares fell 7.6% to $1,186 straight after the release, a sign of how much good news investors had already priced in.

Data centres, modular and labour

On the earnings call, President Trent McKenna said technology work made up 59% of revenue in the first nine months of the year, compared with 42% in the same period of 2025. Modular work was 17% of revenue so far this year, and the company expects more than 4 million square feet of modular space by the end of 2026, rising to about 6 million by the end of 2027.

Management guided to same-store revenue growth in the mid-40% range for 2026 and the mid-20% range for 2027. Asked what that would take, executives were clear that labour, not customer demand, is what limits growth. The company has more than 25,000 employees and expects to keep adding people.

Acquisitions

Comfort Systems remains one of the trade's most consistent acquirers. On 1 August it bought Boys Electrical of Melbourne, Florida, and NeoPod, a healthcare modular business in New Braunfels, Texas, which together are expected to add more than $100m of annual revenue. CFO William George told analysts the pipeline is strong but that "the key to our acquisition program is that we refuse to be hurried" (call transcript).

The bigger picture

Comfort Systems is the clearest public read on US mechanical construction demand, and this quarter says the data centre and advanced-manufacturing build-out is still feeding contractors' order books. The next data point is EMCOR, which reports its third quarter on 29 October.