Why you should, on any job with materials
If you're buying a bathroom suite, a boiler, a pallet of slates or a skip before you're paid a penny, you're lending the customer money. A deposit covers the materials and, just as usefully, it's the customer's commitment: people who've paid a deposit don't cancel on a whim, and people who won't pay one are telling you something.
Direct Line's January 2026 survey found nearly half of UK tradespeople now ask for money up front on larger jobs. It's normal. Customers expect it.
How much
There's no rule, but there is a sensible range. Twenty to thirty per cent is standard on most domestic work. Where the materials are a big share of the price, a bathroom or a kitchen say, ask for enough to cover them; that can be up to half. On a small repair with no parts to speak of, don't bother: the invoice on the day is enough.
Whatever you pick, make it a rule and apply it to everyone. 'I take 25% on every job over £500' is easy to say and nobody takes it personally.
Put it on the quote, in writing
The deposit belongs on the quote, as a line and as a sentence in the terms: how much, when it's due, and what it covers. Agreeing it on the doorstep and never writing it down is how it becomes 'I didn't know I had to pay anything up front'. When the customer accepts the quote they're accepting the deposit with it.
A deposit of 25% (£1,050.00) secures the booking and covers materials. The balance is due on completion. Payment within 7 days of the invoice.
What the law says, for private customers
Two things to know if your customer is a householder rather than a business.
First, the Consumer Rights Act 2015 says your terms have to be fair. A deposit that's wildly more than your real costs, or a 'non-refundable' deposit you keep when you cancel the job, won't stand up. Keep it proportionate and keep it refundable if you're the one who pulls out.
Second, if the contract is made away from your premises, which for a trade is nearly always (their kitchen, your van, a text), the Consumer Contracts Regulations 2013 give them 14 days to cancel. If they want you to start inside those 14 days, get them to ask for that in writing (a text or a tick on the quote is fine). If you start without it and they cancel, you can find yourself unpaid for work done. Put a line on the quote; it takes one sentence.
Make sure it arrives before you spend
A deposit that's been agreed but not paid is just a promise. Don't order materials until the money's in. If it hasn't arrived a few days after they accepted, remind them: it's a job they want done, and the deposit is the thing holding the start date.
Hi Mr Jones, thanks for going ahead with the bathroom. Just a reminder the £1,050.00 deposit is due before I order the suite; bank details are on the quote, reference Q-212. Once it's in I'll confirm the start date. Dean.
Receipt it, and show it on the invoice
When the deposit lands, say so: a one-line text saying it's received and the start date is confirmed. On the final invoice, show the deposit as paid and the balance due, so the customer sees the sum they already paid taken off. Deposits that vanish into a total are the ones that get queried.