Builder asking for a big deposit? What's normal and what's a red flag

You've found a builder you want to work with. The quote is agreed, the start date is pencilled in, and then comes the message: "I'll need 40% up front to secure your slot." Or maybe it was 25%. Or half. Whatever the number, you're now staring at your phone wondering whether this is just how the industry works, or whether you're about to make an expensive mistake.

Here's the honest answer: a builder asking for a deposit is normal, and most requests are made in good faith. But the size of the request, the reason behind it, and how the builder reacts when you ask questions will tell you a great deal about who you're dealing with. This guide covers all three, and gives you the exact words to use when you reply.

The quick answer: what's normal and what isn't

For standard residential renovation work in the UK (extensions, loft conversions, kitchens, bathrooms), a deposit of 10 to 15% of the contract value is reasonable. It covers early materials and shows the builder you're serious, without putting a dangerous amount of your money at risk before anyone has lifted a tool.

Above 25%, you should expect a specific, checkable reason: usually bespoke or long-lead materials that have to be ordered before work starts. "That's just how we do it" is not a reason.

And if a builder wants a 50% deposit on standard work? That's almost never justified. Half the contract value up front means you carry nearly all of the risk while holding none of the leverage. It doesn't automatically mean the builder is dishonest, but it does mean the payment structure is wrong, and it needs to change before you commit.

If you want the full breakdown of deposit amounts by project type, read our guide on how much deposit you should pay a builder, which also covers whether to pay anything before work starts. This article deals with the situation you're actually in: the builder has named a figure, and you need to respond.

Why builders genuinely ask for deposits

It's worth being fair here, because the request usually isn't a trick. Builders ask for deposits for three practical reasons, and understanding them will make your response far more effective.

The first is materials. Most projects need bricks, timber, steel or fixings on site before day one, and suppliers expect to be paid for them. Without a deposit, the builder is financing the opening weeks of your project out of their own pocket, and small firms rarely have the cash reserves to do that across several jobs at once.

The second is booking commitment. When a builder pencils you in, they're turning other work away. Homeowners do cancel, sometimes only weeks before the start date, and a builder who has held a slot open for a job that evaporates loses real money. A deposit makes the booking mutual.

The third is experience. Plenty of good builders have finished a job and then chased the final invoice for months, or watched a client dispute the bill once the scaffolding came down. From their side of the fence, a deposit is proof that your budget is real and that you pay when you say you will. That need is entirely legitimate. And, as we'll cover shortly, there are better ways to meet it than a large bank transfer.

When a bigger deposit is legitimate

Some projects genuinely need serious money before anyone starts work. Bespoke kitchen units are made to order and can take weeks to arrive. Specialist glazing, made-to-measure steel and imported stone all sit in the same category: long lead times, often non-returnable, and useless to the builder if you walk away. It's reasonable for a builder not to want to carry that cost alone, and a deposit above the usual range can be justified in these cases.

But notice what makes it legitimate: a specific cost, for specific items, with a paper trail. So even when a bigger deposit makes sense, two rules apply. First, pay for the materials, not a round percentage. If the kitchen units cost £9,200, the deposit conversation should be about £9,200, not "a third up front" that happens to land somewhere near it. Ask to see the supplier's quote; a builder ordering genuine materials will have one.

Second, consider paying the supplier directly. Many suppliers will happily take payment from you while the builder manages the order and the technical spec. You own the goods from day one, the builder never has to bank your money, and the risk of a deposit vanishing into someone's cash flow drops to zero. A builder with nothing to hide will usually be relaxed about this arrangement.

The red flags in a deposit request

None of the following proves a builder is a cowboy. But each one should slow you down, and two or more together should stop you.

Pressure to decide fast. "The price only holds until Friday" or "I've got someone else keen on your slot" are designed to make you transfer money before you've thought it through. A genuinely busy builder doesn't need to rush you. Manufactured urgency is the oldest trick for switching off someone's judgement.

Cash only. A cash deposit, especially cash in exchange for a discount, leaves you with no paper trail, no payment protection and, in a dispute, no evidence the money ever changed hands.

No written contract. If money is being requested before the terms are written down, you have nothing to enforce if things go wrong. The contract comes first, always.

A deposit not tied to anything specific. If the builder can't tell you what the money covers, the honest answer may be "my cash flow", or worse, the previous client's unfinished project. You don't want your renovation funding someone else's.

Reluctance to discuss stage payments. This is the biggest one. A builder who bristles at the idea of payments tied to completed stages of work is telling you they want your money disconnected from their progress. That's precisely the arrangement you can't afford to agree to.

Exactly how to respond

You don't need to accept or refuse on the spot. Something as simple as "Let me look at the payment side and I'll come back to you tomorrow" buys the time to handle this properly, and gives you a first data point, because a professional will say "no problem".

Then anchor everything on one principle: agree the full payment schedule before any money moves. Try: "Happy to talk about a deposit. Can we first agree the payment schedule for the whole job, so we both know what gets paid when, and what has to be finished first?" Our free stage planner will give you a sensible stage-by-stage starting point in a couple of minutes. For a quick read on the figure itself, our free stage planner compares the deposit with the published guidance.

Next, ask what the deposit actually covers: "What does the deposit pay for? If it's materials, could you send me the supplier quote?" You're not accusing anyone of anything. You're asking a normal commercial question, and the answer will either be specific or it won't.

Finally, offer alternatives to a deposit rather than a flat no. Suggest paying the supplier directly for any big-ticket materials. Ask whether you can pay by credit card. Under Section 75 of the Consumer Credit Act, if any part of a purchase costing between £100 and £30,000 goes on a credit card, the card provider is jointly liable if things go wrong. Not every builder takes card, but it costs nothing to ask. Or propose escrow: the money sits somewhere both of you can see it, secured and visible, and is released as you approve each stage.

A builder hearing this doesn't hear "I don't trust you". They hear "the money is real and the ground rules are clear", which is what the deposit was supposed to establish in the first place.

What protection looks like if you do pay

If you've asked the questions, the answers stack up and you decide to go ahead, protection comes in layers. The minimum is a written contract that states the deposit amount, what it covers, the conditions under which it's refundable, and the stage payment schedule for everything that follows. Pay by a traceable method with a reference linking the payment to the contract (never cash), and use a credit card where you can for the Section 75 cover described above.

You can also keep the deposit out of the builder's bank account altogether. With Renopay, you fund each stage before work on it starts, one stage or several at once. Client funds are held by OPP, an FCA-authorised electronic money institution. Money only reaches your builder as each stage is completed and confirmed. The builder loses nothing they legitimately asked for: before each stage starts, they can see the money for it is real and committed to the project. What disappears is the one part of the arrangement that was never in anyone's interest to defend: your money sitting unprotected in someone else's account before there's any work to show for it.

A fair schedule offends no one

If you take one thing from this article, make it this: a professional builder won't be offended by a fair payment schedule. Most will welcome it, because it protects them from non-paying clients just as it protects you from disappearing deposits. The only people with something to fear from accountability are the ones planning to avoid it.

So if the deposit request survives the questions above, pay it with confidence and enjoy the build. If it doesn't, you've just learned something important, for the price of one slightly awkward conversation rather than half your budget.

Frequently asked questions

How much deposit should a builder ask for in the UK?

For standard residential work such as extensions, loft conversions, kitchens and bathrooms, a deposit of 10 to 15% of the contract value is reasonable. It covers early materials and shows the builder you are serious, without putting much of your money at risk before work starts. Above 25%, expect a specific, checkable reason, usually bespoke or long-lead materials backed by a supplier’s quote.

Is it normal for a builder to ask for 50% upfront?

Not for standard work. Half the contract value up front means you carry nearly all of the risk while holding none of the leverage. It doesn’t automatically mean the builder is dishonest, but the payment structure is wrong and should change before you commit. Ask what the deposit covers, and agree a schedule of payments tied to completed stages of work.

How should I pay a builder’s deposit?

By a traceable method with a reference that links the payment to your written contract, never in cash. The contract should state the deposit amount, what it covers, when it is refundable and the stage payments that follow. Where the builder takes card, a credit card adds Section 75 cover: for purchases between £100 and £30,000, the card provider is jointly liable if things go wrong.

Can I pay the supplier directly instead of giving my builder a deposit?

Often, yes. Many suppliers will take payment from you while the builder manages the order and the technical specification. You own the goods from day one, and the builder never has to bank your money. It suits big-ticket, long-lead items such as bespoke kitchen units, specialist glazing or made-to-measure steel, where the deposit should match the supplier’s quote rather than a round percentage.