Comfort Systems USA Q3 beats with revenue up 54% and backlog at $17.8B, but shares fall 9% on CFO retirement

FIX reported third-quarter 2026 revenue of $3.77 billion after the close on October 22, up from $2.45 billion a year earlier, a 53.7% increase. Net income rose to $489.0 million, or $13.91 per diluted share, from $8.25 a year ago, a 68.6% jump. Both figures beat Wall Street estimates, with revenue about 10.7% above consensus. Operating cash flow reached $1.01 billion, compared with $553.3 million in the same quarter of 2025, according to the company's release.

The backlog is the headline for the longer view. It ended September at a record $17.81 billion, up from $14.06 billion at the end of June and $9.38 billion a year earlier, so it grew about 26% in a single quarter and 90% year over year. Management said these multiyear commitments extend project timelines by 18 to 24 months, and that modular capacity will reach 6 million square feet by late 2027, much of it serving technology customers.

The stock went the other way. Shares fell as much as 13.2% intraday on Friday and closed down about 9%, leaving them roughly 38% below their June high. The Motley Fool tied the reaction to the announced retirement of co-founder and longtime CFO Bill George at year end, with Chief Accounting Officer Julie Shaeff taking the role, and to a sell-the-news pattern hitting AI build-out names this earnings season as some investors anticipate a slowdown in data center spending next year.

What to watch: how quickly the backlog converts to revenue, whether 2027 margins hold in what the CFO called strong ranges, and how the CFO handoff goes. Management said it expects continuing growth into 2027, so the gap between that outlook and Friday's price action is a read on how much AI capex risk the market is now assigning to contractors exposed to data centers.