UK · 2026

What should a plumbing firm charge per hour?

There is no universal number, and anyone quoting you one is quoting somebody else's costs. What there is, is a method: take the wage, add what employing someone actually costs, divide by the share of paid hours you invoice, then add vans and overheads. That gives the rate below which an hour loses money. It takes an evening and it is worked in full below.

The short answer

01Your floor is the cost of an hour of capacity, not a price.
02Wage + employment on-costs = what a paid hour costs.
03Divide by the share of paid hours that reach an invoice — this step is the one most firms skip, and it is the largest.
04Add vans and overheads, each spread over the firm's invoiced hours for a year.
05The result is your floor. A charge-out rate is that plus materials, risk and profit.

Why isn't there a single right answer?

Because the largest term in the calculation is one nobody publishes: the share of the hours you pay for that actually end up on an invoice. Two three-van firms in the same county, paying the same wage and carrying the same overheads, will have floors 33% apart if one invoices 20 hours a week per head and the other invoices 30. Neither is doing anything wrong. They are different businesses.

So a published “average hourly rate for a plumber” is a survey of prices, which tells you what customers in that area have been willing to pay. That is genuinely useful — it is the ceiling you are working under. It is not the floor you are working above, and only one of those two numbers can bankrupt you.

The arithmetic, worked in full

A three-van firm with employed engineers, at figures that would not raise an eyebrow in 2026. Every line is computed from the six inputs below — change them to yours and the method is identical.

The inputs

Bare wage£21.00/hour

Hours paid for40/week each

Hours invoiced25/week each

Engineers3

Vans£105/week each, 3 vans

Overheads£2,600/month

Step 1

The wage you pay£21.00/hr

Step 2

Plus employment on-costs£27.31/hr

£21.00 × (1 + 15.00% + 3.00% + 12.07%) = £27.31

Employer's NI at 15.00%, pension at 3.00%, and 28 days of statutory leave spread over the 232 days worked, which is 12.07%. Add sick pay, employer's liability, tools and training if you carry them — most firms do, and leaving them out flatters the floor.

Step 3

Divided by the share of paid hours you invoice£43.70/hr

£27.31 ÷ 62.5% = £43.70

25 invoiced out of 40 paid. The 15 hours in between — driving, quoting, the merchants, the customer who wasn't in — are paid for and have to be carried by the hours that do get invoiced.

Step 4

Plus vans, per invoiced hour£4.20/hr

£105 × 3 × 52 = £16,380/yr ÷ 3,900 hrs = £4.20

The divisor is the whole firm's invoiced hours: 25 × 3 × 52 = 3,900.

Step 5

Plus overheads, the same way£8.00/hr

£2,600 × 12 = £31,200/yr ÷ 3,900 hrs = £8.00

The floor, per invoiced hour£55.90/hr

That is the floor, not the price. At £55.90 an hour this firm breaks even on labour and stands still. A charge-out rate has to carry the work you quoted and didn't win, the jobs that come back, and a profit — 15% would be £64.29, 25% would be £69.88, 35% would be £75.47. Which of those is right is a judgement about your market, and this page cannot make it for you.

How much does being busier change it?

More than any other input, because invoiced hours divide all three parts at once. Everything below is the same firm with the same costs — only the hours move.

Invoiced hours a week, each	Utilisation	Floor	Against the example
18	45.0%	£77.64/hr	+39%
20	50.0%	£69.88/hr	+25%
22	55.0%	£63.53/hr	+14%
25 — the example	62.5%	£55.90/hr	—
28	70.0%	£49.91/hr	-11%
30	75.0%	£46.59/hr	-17%
33	82.5%	£42.35/hr	-24%

Read it the other way round as well: if you are quoting against a competitor who is meaningfully cheaper, one explanation is that they are busier, not that they are reckless.

What this number doesn't tell you

Materials pass through, and shouldn't be in the rate

A boiler swap and a tap washer can consume the same two hours and hundreds of pounds apart in parts. Fold materials into an hourly rate and you overcharge the light jobs, undercharge the heavy ones, and lose the ability to see which is which. Price materials at cost, separately, and let the hourly figure carry only time.

Some job types are too thin to price from

If you did nine bathroom installs last year, the average of nine jobs is not a price — it is an anecdote with a decimal point. Where the evidence is thin the honest answer is a rule (hours at your floor, plus materials at cost) rather than a fixed ticket.

One year is a position, not a trend

A single twelve-month window tells you where you stand. It cannot tell you whether you are drifting, because it has nothing to compare against. Two years does; one does not, and any claim about direction from a single year is a claim about noise.

Your invoiced-hours figure is probably optimistic

This is the number owners are most confident about and most often wrong about. Almost everyone estimates high. Take it from records — actual hours that appeared on actual invoices — rather than from a sense of how the week went, because the whole calculation hangs off it.

Working out yours

Everything above is on the floor rate page in more detail, including how to gather the six inputs and the two mistakes that account for most wrong answers. It is free, it is the same method we run, and for a firm with tidy records it is an evening's work.

What we sell is that method applied to twelve months of your actual jobs — every type costed against the hours it consumed, every figure marked with the record it came from, and a person reading the finished document against your data before it reaches you.

Or have it worked out on your own year.

£500 / $650 · 12 months of your jobs · 5 working days · refunded in full if nothing material is found