How does flat-rate pricing math work?
Break-even per billable hour = yearly operating costs ÷ billable hoursRate to bill = break-even ÷ (1 − profit target) ÷ (1 − discount room)Flat rate = hours × rate + parts × (1 + markup)
With the defaults: $500,000 ÷ 3,132 = $159.64. Then $159.64 ÷ 0.80 ÷ 0.85 = $234.77 an hour. A 3.5-hour, 50-gallon gas water heater swap with $850 in parts: 3.5 × $234.77 + $850 × 1.5 = $2,097.
Most of the work is in the hourly rate. Operating costs here means everything except the materials you bill on jobs, the way the forum example counts it: tech pay and payroll costs, trucks, office staff, rent, insurance, software, marketing and a salary for you.1 Divide by the hours your plumbers actually bill, and you have what each billable hour costs the business before anyone earns a dollar.
Then the price book is multiplication. Each task gets the hours it really takes, drive and setup included, times your rate, plus parts at your markup. The customer sees one price before the work starts. When a tech beats the book time, you keep the difference; when a job runs long, you eat it. That's why the book hours need to come from your own jobs.
Already use a price book in ServiceTitan, Housecall Pro or Jobber? Put the step 1 rate in as the labor rate it multiplies. The task times stay yours.
Margin or markup: which one is your profit target?
Owners mix these up all the time, and it costs real money. Margin is profit as a share of the price. Markup is profit as a share of cost. A 20% margin needs a 25% markup.
| What you do to the $159.64 break-even | Rate | Profit kept, % of price |
|---|---|---|
| Multiply by 1.20 (a 20% markup) | $191.57 | 16.7% |
| Divide by 0.80 (a 20% margin) | $199.55 | 20% |
| Divide by 0.80, then by 0.85 for discount room | $234.77 | 32% at full price, 20% at 15% off |
Our arithmetic on the forum example.1 Profit here is what's left after all operating costs.
Parts are usually priced by markup. Most plumbing businesses mark parts up 40 to 60%, according to a 2026 field-software pricing guide.3 A 50% markup on a $850 water heater adds $425, which is a 33.3% margin on the parts line. If your target is a margin, set it as a margin.
How should you price after-hours work and member discounts?
After hours. Charging more at night and on weekends is common practice. A 2026 plumbing pricing guide works its example at 1.5 times the normal rate and lists 1.5 to 3 times for after-hours, holiday and emergency work.3 The calculator defaults to 1.5 times on the labor part of the price and leaves parts at the normal sell price; that split is our choice. At the default rate, the water heater swap goes from $2,097 to $2,508 after hours. Whatever multiplier you pick, it has to cover overtime or on-call pay for the plumber who goes out, and the call has to get answered to earn it.
Members. A field-software vendor's 2026 guide puts the usual maintenance-plan repair discount at 10 to 15% off flat-rate prices.2 The safe way to offer one is to build the room into the rate first, as step 1 does. At a 15% discount room and a 15% member discount, members still leave your full 20% profit target on labor, and everyone else pays the price that funds it. If the member discount is bigger than the room in your rate, the calculator flags it.
Price the trip too. A flat rate quoted at the door usually includes the drive, so the hours for each task should include it. Shops that charge a separate trip or diagnostic fee can set that up as its own task in step 2.
How many billable hours does a plumber really have?
Fewer than the 2,080 hours you pay for, and this one number moves your rate more than any other. Billable hours are the hours on a customer's invoice. Drive time between calls, parts-house runs, callbacks, estimates that don't close, meetings and slow afternoons all get paid and none get billed.
- The forum example assumes 4 billable hours a day for 261 working days: 1,044 a plumber, about half of an 8-hour day.1
- A 2026 field-software guide uses a plumber who is paid for 40 hours and bills 25 of them, about 62%.3
- Published benchmarks are thin. One field-software vendor notes that the 65 to 75% utilization range quoted around the web "rarely traces back to primary data."4 A 2007 Plumbing & Mechanical column put the ratio of hours billed to hours paid anywhere from 20% to 100%, depending on the company.5
So use your own. Your field software can total invoiced labor hours by tech for the last 12 months; divide by the hours you paid them. Then try it here: at the defaults, one more billable hour a day per plumber drops the rate you need from $235 to $188. That's the case for tighter routing and fewer wasted trips, before you touch the price.
Worked example: $500,000 in costs and three plumbers
Someone asked on a field-software community forum how flat-rate pricing works for a plumbing company. One reply worked it like this:1
- Costs. $500,000 in yearly operating expenses, not counting materials.
- Billable hours. 4 a day × 261 days = 1,044 a plumber; three plumbers = 3,132.
- Break-even. $500,000 ÷ 3,132 = $159.64 per billable hour.
- Profit. ÷ 0.80 for a 20% margin = $199.55.
- Discount room. Or ÷ 0.68 (0.80 × 0.85, room for a 15% discount) = $234.77. The thread shows $234.76 because it rounds the break-even first.
Carry that into a price book with our example times and parts, at a 50% parts markup:
| Task | Standard | Member, 15% off | After hours, labor × 1.5 |
|---|---|---|---|
| Toilet rebuild | $295 | $251 | $412 |
| Kitchen faucet replace | $355 | $302 | $472 |
| Water heater, 50-gal gas tank | $2,097 | $1,782 | $2,508 |
| Main line clear from cleanout | $367 | $312 | $543 |
| Garbage disposal replace | $460 | $391 | $577 |
Example times and parts from the calculator defaults; use yours. Our arithmetic.
The water heater swap, for example: 3.5 hours × $234.77 = $822 of labor and $1,275 of parts at a 50% markup, $2,097 in all. Counting tech pay of $79.82 per billable hour ($250,000 ÷ 3,132) and the parts, its gross margin is 46%. After its share of every operating cost, it leaves $688 at the standard price and $373 at the member price.
How do your prices compare with what homeowners see?
Homeowners look up a job before they call, and the consumer cost guides are what they find. Use those ranges as a sanity check for your price book. They're national figures that blend cheap and expensive markets, and they often run below what a licensed shop invoices.
| Task | Example hours, parts | Example price | What homeowners see in cost guides |
|---|---|---|---|
| Toilet rebuild | 1 h, $40 | $295 | $150 to $391, average $271 (toilet repair)6 |
| Kitchen faucet replace | 1 h, $80 | $355 | $162 to $364, average $2627 |
| Water heater, 50-gal gas tank | 3.5 h, $850 | $2,097 | $900 to $2,500 for gas, average $1,8008 |
| Main line clear from cleanout | 1.5 h, $10 | $367 | $350 to $650, average $4759 |
| Garbage disposal replace | 1 h, $150 | $460 | $200 to $625, average $55010 |
Example prices at the default rate of $234.77 and a 50% parts markup. Cost-guide ranges from HomeAdvisor (June 2026) and Fixr (2025 and 2026). Fixr puts a standard water heater swap at 2 to 4 hours of plumber time.8
At the example rate, all five example prices sit inside the cost-guide ranges, the faucet and the main line near the edges. A price well above the range isn't wrong if your hours and costs are real, but expect more homeowners to ask about it on the phone.
Next: does Google send the calls this sheet assumes?
This sheet assumes a certain number of calls a month. The free 49-point map scan shows whether Google sends them: where your company shows up for a money search like "plumber" or "water heater replacement" across your service area, with a quick website check, in 2 business days.
The Booked-Job Audit ($1,500) scores 20 recorded calls and traces calls to booked work, so you can see which calls became jobs at these prices. After-Hours Capture, part of the Growth Program ($2,000 a month), goes after the night and weekend calls you price at the after-hours rate: emergency search visibility by time of day, plus how those calls get answered and booked. Get the free map scan or book a 15-minute call.
Wondering what the calls you miss cost at these prices? The Missed Call Check does that math for plumbing, nights and weekends included.
Questions owners ask
How do I calculate a flat rate for a plumbing job?
Start with your hourly rate to bill: yearly operating costs divided by billable hours, then divided by one minus your profit target. Multiply it by the hours the job takes, drive and setup included, and add parts at your markup. At $234.77 an hour, a 1-hour toilet rebuild with $40 in parts at a 50% markup is $295.
What hourly rate should a plumbing company charge?
The one your costs and billable hours call for. In a worked example from a contractor forum thread, $500,000 of costs over 3,132 billable hours came to $159.64 to break even and about $235 with a 20% profit target and 15% room for discounts.1 A shop with lower costs or more billable hours needs less.
What's the difference between margin and markup?
Margin is profit as a share of the price; markup is profit as a share of cost. A 20% margin needs a 25% markup. Multiplying a $159.64 break-even by 1.20 gives $191.57, which keeps only 16.7% of the price.
How much should a plumber mark up parts?
Most plumbing businesses use 40 to 60%, according to a 2026 field-software pricing guide.3 The calculator defaults to 50%, which is a 33.3% margin on the parts line. Many shops use a sliding scale, with a higher markup on small parts and a lower one on water heaters and other big-ticket items.
How much more should I charge after hours?
1.5 times the normal rate is common; one 2026 plumbing pricing guide lists 1.5 to 3 times for after-hours, holiday and emergency work.3 Make sure the premium covers overtime or on-call pay, and that the phone gets answered at night so you earn it.
How big a discount should maintenance plan members get?
10 to 15% off flat-rate prices is typical, according to a field-software vendor's 2026 guide.2 Build the room into your rate first, so members still leave your profit target. If the member discount is bigger than that room, they don't.
How many billable hours does a plumber have in a year?
Far fewer than the 2,080 hours you pay for. A contractor forum example used 4 billable hours a day for 261 days, 1,044 a year.1 A 2026 field-software guide uses 25 billable hours out of 40 paid.3 Pull your own from invoiced labor hours in your field software.
Should a flat rate include drive time?
Yes, if you quote one price at the door. Put drive and setup into each task's hours. If you charge a separate trip or diagnostic fee, add it as its own task so it shows on the price card.
Does this calculator save what I type?
No. The math runs in your browser and your numbers aren't sent to us. The copy-link button copies a link that holds your numbers and tasks, so you can share them. If you email yourself the link, it comes to us so we can send it.
Sources
Defaults on this page: yearly operating costs, billable hours (4 a day for 261 days for 3 plumbers), the 20% profit target and the 15% discount room come from a worked example in a flat-rate pricing thread on a field-software community forum, which counts operating expenses without materials1; the cost build-up starts from the BLS median wage for plumbers, pipefitters and steamfitters (May 2025) plus a 30% load we assume11; the parts markup (50%, inside a 40 to 60% range) and the 1.5 times after-hours multiplier come from a 2026 field-software pricing guide, a vendor source we rate low3; the 15% member discount sits at the top of the 10 to 15% range in a field-software vendor's 2026 guide.2 Truck, overhead and owner-pay lines, the example task times and parts, and applying the after-hours multiplier to labor only are our assumptions. Cost-guide ranges are shown as a sanity check only.6,7,8,9,10 Profit and discount room are taken as shares of price (rate = break-even ÷ (1 − profit) ÷ (1 − room)). Gross margin on a task counts tech pay per billable hour and parts; "left after all costs" counts break-even per billable hour and parts. Figures are rounded to the dollar on screen; the hourly rate is shown to the cent.
- How does flat rate pricing work for a plumbing company? (community thread; a reply works $500,000 in yearly operating expenses over 3,132 billable hours). Jobber Community, accessed Oct 19, 2026. community.getjobber.com/discussions/service-based-skilled-trades/how-does-flat-rate-pricing-work-for-a-plumbing-company/12347
- How to sell plumbing maintenance agreements (repair discount typically 10–15% off flat-rate pricing). Simpro, Aug 25, 2026. www.simprogroup.com/blog/sell-plumbing-maintenance-agreements
- Housecall Pro pricing (Basic $59/$79, Essentials $149/$189, Max $299/$329 a month, annual/monthly billing). Housecall Pro, accessed Oct 19, 2026. www.housecallpro.com/pricing/
- Technician utilization rate: how to measure billable efficiency. Simpro, Oct 9, 2026. www.simprogroup.com/blog/technician-utilization-rate
- The remaining piece in the profit puzzle (efficiency factor: hours billed ÷ hours paid; 20% to 100% across companies). Plumbing & Mechanical, Nov 1, 2007. pmmag.com/articles/91313-the-remaining-piece-in-the-profit-puzzle-br-maurice-maio
- How much does toilet repair cost? (average $271, normal range $150 to $391). HomeAdvisor, Jun 19, 2026. www.homeadvisor.com/cost/plumbing/repair-a-toilet
- How much does it cost to replace a kitchen faucet? (average $262, normal range $162 to $364). HomeAdvisor, Jun 17, 2026. homeadvisor.com/cost/plumbing/install-a-faucet
- How much does it cost to install a 50-gallon water heater? (average $1,800). Fixr, Jan 26, 2026. www.fixr.com/costs/50-gallon-water-heater
- Cost to unclog a main sewer line ($350 to $650, average $475). Fixr, Jan 31, 2025. www.fixr.com/costs/unclog-main-sewer-line
- How much does it cost to replace a garbage disposal? (average $550, normal range $200 to $625). HomeAdvisor, Jun 19, 2026. www.homeadvisor.com/cost/appliances/garbage-disposal-replacement-cost
- Occupational Outlook Handbook: Plumbers, pipefitters, and steamfitters (median pay $63,800 a year, May 2025). U.S. Bureau of Labor Statistics, accessed Oct 19, 2026. www.bls.gov/ooh/construction-and-extraction/plumbers-pipefitters-and-steamfitters.htm