Where plumbing contractors lose money
7 things cost plumbing contractors money without ever showing up as a line item, and each one traces to a step you can install. Plumbing contractors average 25% gross margin, 16% overhead and 9% net profit at $1M–$5M of revenue. The CFOS target at that size is 26% gross margin, 15% overhead and 11% net, and the gap of 2 points on the bottom line is where those mechanisms live. Figures for all 7 revenue bands are in the table below.
Plumbing sits 1st of 7 in mechanical and life safety on net profit, and it carries heavier overhead than the 48-trade average. Here is every figure, across all 7 revenue bands.
Plumbing by revenue band
| Metric | $1M–$5M | $5M–$10M | $10M–$25M | $25M–$50M | $50M–$100M | $100M–$500M | $500M+ | CFOS target |
|---|---|---|---|---|---|---|---|---|
| Overhead | 16% | 15% | 14% | 13% | 12% | 11% | 10% | 15% |
| Gross margin | 25% | 26% | 27% | 28% | 30% | 31% | 33% | 26% |
| Net profit | 9% | 11% | 13% | 15% | 18% | 20% | 23% | 11% |
SPM The Construction CFO. SPM Trade Benchmark Reference: Plumbing. 2026. Sulphur Prairie Management, LLC. https://runoncfos.com/trades/plumbing. CC BY 4.0.
Figures on this page were last revised 2026-08-21. Published under CC BY 4.0, which permits reuse of any figure here, including commercially, as long as the credit above travels with it. The same figures in machine-readable form: /benchmarks.json.
Trade level gross margin and overhead compiled by SPM The Construction CFO, validated against published CFMA and JMCO benchmarks. The CFOS targets beside them are from the book CONTROL: The Construction Financial Operating System, published with the full reference at runoncfos.com.
- 2024 Construction Financial Benchmarker, Executive Summary, Construction Financial Management Association, 2024.
- 2025 Performance Benchmarks, Construction Companies, Jones Maresca and Company, 2025.
- SPM Trade Benchmark Reference, Sulphur Prairie Management, LLC, 2026.
Sourcing and method: the methodology page.
Which bands are measured. The 4 bands above $10M–$25M carry the survey curve further out and have not been reconciled against the licensed CFMA Benchmarker. How every figure was built is set out on the methodology page.
7 problems specific to plumbing
The domestic hot water plant is 30 weeks out, the rep wants a big number at release, and the unit doesn't get set until the mechanical room is finished at the very end of the job. The underground is holding test and ready to cover, the pump truck is scheduled, and the inspector's first open slot is after the pour date. You bid copper in March, bought it at buyout in September, and the escalation language you fought for only protects half the scope. You were in the dirt before the steel got there, and you'll see that retention when the building opens.
Each one below points at the item, the unit, the clock, or the party that makes it a plumbing problem, and it says which step fixes it.
| Mechanism | Why it's specific to this trade | Step |
|---|---|---|
| Your Water Heater Deposit Goes Out Eight Months Early | Electrical gear gets long lead attention from everybody, because energizing the building sits on the GC's own critical path and the release date appears in his schedule and his phone calls. Plumbing source equipment sets after the building is basically built, so nobody upstream tracks your release date until the unit is late and the CO is at risk. That leaves the longest lead time and the last billable activity attached to the same package, with the plumber financing all of it alone. | Project management |
| Concrete Is Booked Thursday and Inspection Opens Monday | No other trade's inspection sits between a general contractor and a concrete pour, so the whole slab schedule pushes against one plumbing sign off. Drywall, paint, and tile get inspected while the work is still visible and fixable. Plumbing gets inspected at the one moment when the next step makes the work permanent, which is why the underground phase generates standby time and buried liability that no other scope on the job produces. | Project management |
| Copper and Resin Move Apart and Your Bid Covers One | Most trades carry one input. A framer watches lumber and a roofer watches asphalt. A site contractor tracks diesel along with pipe. Plumbing is the scope where a metals market and a petrochemical market both live inside the same lump sum, on the same schedule of values, and where the usual substitution play moves material out of one curve while leaving the fixture package sitting squarely in the other. | Estimating system |
| You Earn It in Month Two and Collect in Month Twenty-Six | Plumbing goes in the ground first and trims out last, and no other trade on the job carries both ends. A site contractor bills early and closes out early. A finish trade bills late, then waits a short time for release. Plumbing bills at the front of a two year schedule and collects at the back of it, so the retention on your earliest and most exposed work sits the longest and funds somebody else's project the entire time. | Monthly cadence |
| You Restart the Job Five Times and Price One of Them | Most subs mobilize once, maybe twice. Plumbing follows the structure of the building itself, so the schedule pulls you back every time a new condition is ready, and the time between visits gets filled with other jobs. The restart cost is real labor, it happens five times, and it hides completely because the whole contract runs on one cost code with no split between underground, rough, and trim. | Job cost structure |
| Every Leak Comes Back to Your Job Cost | Plumbing installs early, sits in everyone's way for months, then disappears inside the building while other trades work directly on top of it. That combination of long exposure and total concealment belongs to piping, and it means your damage gets discovered at the worst moment by the worst symptom. The general contractor takes the shortest path to a dry building, and that path runs straight through your invoice. | Standards and accountability |
| A Thirty Dollar Fitting Writes a Five Figure Check | Every trade has warranty work. Plumbing is the one where the defect keeps running 24 hours a day until somebody finds it, and where the damage is almost entirely to other people's scope. That's why a plumbing callback becomes a property damage claim with a deductible and a loss run behind it, and why the cost hits a period so far from the job that nobody ever ties the two together. | Overhead calculation |
Plumbing against the other 47 trades
| Metric | Plumbing | Mechanical and life safety average | All 48 average | Rank |
|---|---|---|---|---|
| Overhead | 16% | 16.1% | 15.1% | 32nd of 48 |
| Gross margin | 25% | 24.6% | 22.1% | 5th of 48 |
| Net profit | 9% | 8.4% | 7% | 2nd of 48 |
Plumbing sheds 6 points of overhead between $1M–$5M and $500M+, against 6.3 for mechanical and life safety as a group. Inside that group, Mechanical, Plumbing and Elevator all keep 9%, the most in the group, and Fire protection runs the leanest overhead at 15%. The first of those is this trade.
Other mechanical and life safety trades
What owners ask
What overhead should a plumbing contractor run?
Plumbing shares its overhead figure with 12 other trades at this revenue, which is what the published data resolves to. It runs 16% at $1M–$5M and 10% at $500M+, as a percentage of revenue. That sits 0.1 points below the mechanical and life safety average of 16.1%. The CFOS target at $1M–$5M is 15%. The CFOS target is one point leaner than your trade's average at your revenue.
What gross margin should a plumbing contractor run?
Plumbing shares its gross margin figure with 2 other trades at this revenue, which is what the published data resolves to. It runs 25% at $1M–$5M and 33% at $500M+, as a percentage of revenue. That sits 0.4 points above the mechanical and life safety average of 24.6%. The CFOS target at $1M–$5M is 26%. The CFOS target is published at $1M to $5M. It's set at whatever gross margin produces the net profit target once overhead is paid, and never below your trade's own average.
What net profit should a plumbing contractor run?
Plumbing shares its net profit figure with 5 other trades at this revenue, which is what the published data resolves to. It runs 9% at $1M–$5M and 23% at $500M+, before taxes, as a percentage of revenue. That sits 0.6 points above the mechanical and life safety average of 8.4%. The CFOS target at $1M–$5M is 11%. The CFOS target is published at $1M to $5M.
What profit margin should a small plumbing business run?
Owners usually mean net profit when they say profit margin, and for plumbing at $1M–$5M that's 9%. Gross margin is a different number, 25%, and it's what's left after job costs but before overhead. Overhead is the 16% sitting between the two. A small plumbing business holding 9% net is at the published figure for its size, and the CFOS target at that revenue is 11%.
Does plumbing get more profitable as it grows?
Overhead is the number that moves. Plumbing sheds 6 points between $1M–$5M and $500M+, which is in line with the 6.3 points mechanical and life safety sheds as a group. Net profit is already above the 48-trade average, so the room is in holding it while revenue climbs.
Where does plumbing sit against the other trades?
Plumbing ties 2 trades in mechanical and life safety on net profit, all at 9%. Nothing publishes more, and Mechanical and Elevator match it. Fire protection runs the leanest overhead at 15%. Gross margin ranks 5th of 48 and overhead ranks 32nd.
Everything on this page is something you can install yourself, andCONTROL is the order to do it in. If you would rather buy the finished result, SPM The Construction CFO does this work for plumbing contractors as a service. It is a separate firm, Sulphur Prairie Management, LLC, run by the same author.
Wrote CONTROL, the 8 step system these figures sit inside. More about the author.