A customer asks why the boiler on your quote costs more than the one they found online. It is a fair question, and most tradespeople answer it badly — either by apologising and dropping the price, or by getting defensive about a number they never worked out in the first place.

You are not selling them a box. You are selling them the right box, on site, on the day, with someone standing behind it.

What the markup actually pays for

Between the merchant's price and the customer's invoice sits work that nobody itemises:

  • Knowing what to buy. The right part, the right size, the right spec for the job and the regulations.
  • Getting it. The trip to the merchant, the wait at the counter, the second trip when the first delivery was wrong.
  • Carrying the cost. You paid in June. The customer pays in July, or September.
  • Waste and breakage. You buy eleven and use ten.
  • The guarantee. If the part fails in eight months, you go back, and that visit is free.

Charge materials at cost and you do all of that for nothing, then pay for the return visit out of your own pocket.

Markup and margin are not the same number

This catches people out every week, and it always costs money in the same direction.

Markup is added to what you paid. Margin is what you keep out of what you charged.

Buy a part for £100 and add 20% markup, and you charge £120. Your margin is not 20% — it is £20 out of £120, which is 16.7%.

To actually keep 20%, you charge £125. Small on one part, real across a year of materials.

To turn the margin you want into the markup you add: divide the cost by (1 minus the margin).

  • 20% margin → charge cost ÷ 0.8 → a 25% markup
  • 25% margin → charge cost ÷ 0.75 → a 33% markup
  • 30% margin → charge cost ÷ 0.7 → a 43% markup

So what is the right number?

There is no legal rate and no industry standard anyone can hold you to. What there is, is a sensible range, and a set of reasons to sit at one end of it.

Most UK trades work somewhere between 10% and 30% on materials. Where you sit depends on four things.

1. How much of the job is materials

A rewire is mostly labour with a modest materials bill. A kitchen fit can be the other way round. The bigger the materials share, the more a small change to the markup moves the whole job, and the more visible it is to the customer.

2. How much work the sourcing takes

Standard stock off the shelf earns the lower end. A specified item you had to track down, price up, collect from a supplier forty miles away and store in your garage for a fortnight earns the higher end.

3. What your discount is

If you buy at trade prices, part of your markup is already in your pocket before you add anything. That is not a reason to skip the markup. It is the reward for having an account, a history and a relationship the customer does not have.

4. What the risk is

The more expensive the item and the longer its guarantee, the more that return visit could cost you. Price the risk you are carrying.

The arithmetic, on a real job

A bathroom. Materials cost you £2,400. Three days' labour at £320 a day is £960.

  • At cost: £3,360 invoiced, £960 to you. One wrong delivery and half a day chasing it, and the job pays £640 for three days.
  • At 20% markup: £2,880 of materials, £3,840 invoiced, £1,440 to you. The extra £480 covers the trips, the waste and the come-back.

Twelve bathrooms a year is the difference between £11,520 and £17,280 — for the same work, the same days and the same customers.

How to put it on the quote

You have a choice, and it matters more than the percentage.

A single price for the work — materials and labour together, one figure, one job. Nobody can line-shop it against the internet. This is what most established trades do.

Itemised — every part listed with a price. Honest, and useful on big jobs, but it invites the conversation about the boiler they found online, and it teaches the customer to price your supply chain instead of your work.

A middle path works well: quote the job as a price, and be ready to explain what is in it if asked. Being able to explain is the point. A number you chose for a reason survives the question; a number you made up does not.

The one thing not to do

Do not hide the markup by inflating the hours. It corrupts the only figure you have that tells you how long work really takes, and next time you price that job you price it from a lie.

Check it against reality

The markup you set is a guess about waste, trips and come-backs. Only your finished jobs say whether it was the right guess.

Track what you estimated for materials against what you actually spent, on job after job. If you are consistently over, the markup is too thin or the estimate is. Both are fixable, and neither is visible if the receipts live in the van.

How Nule helps

Quote the materials, run the job, and see the two side by side when it is finished.

  • Materials logged against the job as you buy them, receipt and all.
  • Estimated against actual, on every job, so the markup is tested and not assumed.
  • Patterns across jobs: the work where your materials always run over, and by how much.

The right markup is the one your own finished jobs say you need.

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