How much deposit should you pay a builder in the UK?

You have agreed a price with your builder, the start date is locked in, and now they have asked for a deposit. The question is not whether the request is reasonable (in most cases it is), but how much is appropriate and what protections should be in place before you pay it.

Deposit norms vary across the UK construction industry, and there is no statutory limit on what a builder can ask for. This makes it particularly important to understand what is typical, what should raise concerns, and how to structure the payment so your money is protected.

Should you pay a builder a deposit upfront?

Usually, yes, as long as it is proportionate and written into a contract. Most residential builders run on thin margins with real costs before day one: a kitchen extension needs structural steel, blocks, concrete and timber on site before any labour starts, and suppliers expect payment within about 30 days. Without a deposit, the builder is financing your project from their own cash flow, and their site team still has to be paid every week.

The risk is on your side. Once a deposit reaches a builder's bank account, getting it back in a dispute is slow, and harder still if the business fails. So the question is less whether to commit money and more how to commit it safely. You have three main options:

• Pay a capped deposit under a written contract, as set out in the rest of this guide.
• Buy the first-stage materials yourself and have them delivered to site, so you own the goods. This works best on simpler projects, or when you have a project manager who knows exactly what to order.
• Pay for each stage before it starts, with the money held securely until the stage is approved, so the builder can see it is there without it sitting in their account. On larger projects, a quantity surveyor or independent project manager can also certify each stage before it is paid.

Our guide to alternatives to paying a builder a deposit compares these in more detail.

What is a normal builder deposit in the UK

For most residential renovation projects in the UK (extensions, loft conversions, kitchen refurbishments, bathroom renovations), a deposit of 10% to 15% of the total contract value is a sensible ceiling. On a £50,000 extension, that means £5,000 to £7,500.

This range makes sense because it broadly corresponds to the cost of materials needed for the first stage of work, plus a small margin for the builder's mobilisation costs (site setup, skip hire, equipment delivery). It is enough to demonstrate the homeowner's commitment without exposing them to excessive risk.

Some builders ask for a fixed amount rather than a percentage: for example, a flat £2,000 or £5,000 regardless of project size. This can be reasonable on smaller projects but should be evaluated against the total contract value. A £5,000 deposit on a £15,000 bathroom renovation is 33%, which is on the high side.

For an extension specifically, you can check the deposit against what each stage of an extension involves and what it typically costs, rather than relying on a rule of thumb alone.

Deposit amounts that should raise questions

Any deposit request above 20% of the total project value warrants a direct conversation about what the money is for. If the builder can provide a detailed breakdown (for example, £8,000 of bespoke joinery that must be ordered eight weeks in advance, or £6,000 of structural steel with a long lead time), the higher deposit may be justified by genuine material costs.

If the explanation is vague ("we need it to get started" or "it's just how we work"), proceed with caution. A builder who cannot explain where your deposit is going may be relying on incoming deposits to fund work on other clients' projects. This is not sustainable, and you do not want to be the homeowner left holding the bill when the cycle breaks.

Deposits of 30% or more with no material-cost justification are a significant red flag. At that level, you should seriously consider whether this is the right builder for your project, regardless of how good their portfolio or reviews look. Our guide on checking a builder and the warning signs to watch for covers this in detail.

How to verify what the deposit is actually paying for

Ask your builder to provide an itemised breakdown of the deposit. This should list specific materials, their suppliers, unit costs, and delivery dates. If the deposit includes a labour element, that should be specified separately.

Cap the deposit at the cost of the first stage's materials plus a reasonable margin. If the builder quotes £5,000 for first-stage materials, a deposit of £5,000 to £6,000 is proportionate. A deposit of £15,000 on a £60,000 project where the first stage's materials cost £5,000 is not. Our free stage planner shows where any deposit request sits against the published Citizens Advice, Checkatrade and MyBuilder guidance.

Cross-reference the material costs against the Renopay stage planner or by requesting quotes directly from suppliers. Builders buy materials at trade prices, so their costs will typically be below retail, but the overall figures should be in the right ballpark.

For projects where the deposit is funding bespoke or long-lead items (structural glazing, handmade kitchen units, imported stone), ask whether you can pay the supplier directly. This way the builder gets the materials they need, you retain ownership of the goods until they are installed, and the deposit risk is transferred from the builder's bank account to a tangible asset on site.

What your contract should say about deposits

Before paying any deposit, ensure your contract addresses the following points.

The exact deposit amount and what it covers, ideally referencing the itemised breakdown described above. The conditions under which the deposit is refundable, for example if the builder fails to start work by the agreed date or abandons the project. The payment schedule for the remainder of the project, structured as stage payments tied to completed milestones. And the process for handling disputes about deposit refunds, including any agreed alternative dispute resolution mechanism.

Under the Consumer Rights Act 2015, a builder who takes a deposit and fails to provide the agreed service is in breach of contract, and you are entitled to a remedy. But relying on the Act after the fact is slower and more painful than having clear contract terms that prevent the dispute in the first place.

The escrow alternative to direct deposits

The fundamental problem with deposits is that the money leaves your control before the work begins. Once it is in the builder's account, recovery depends on their goodwill, their solvency and, if those fail, the court system.

Milestone payment platforms such as Renopay work on the same principle as escrow. Instead of transferring the deposit directly to the builder, you fund the first stage and the money is held securely. The builder has proof that the money exists and is committed to the project. But the funds are not released until you approve the first milestone (the work the deposit was intended to fund).

This removes the deposit dilemma entirely. The builder knows the money is there. The homeowner knows it is released when the work is approved. Neither side is taking a leap of faith. For homeowners who have read about builders disappearing with deposits and want a structural safeguard against that scenario, holding each stage's money securely is a strong one.

What happens if you need to recover a deposit

If you pay a deposit and the project goes wrong (the builder fails to start, delivers substandard work, or abandons the project), recovering that money depends on how it was paid and what your contract says.

For deposits paid by bank transfer directly to the builder, your route is through the courts. Claims up to £10,000 go through the small claims track, which is designed to be accessible without a solicitor. The court fee depends on the claim value. You will need to demonstrate that the builder breached the contract terms and that you are owed a specific amount.

The challenge is enforcement. Winning a county court judgment does not mean you will be paid. If the builder has dissolved their company, moved abroad, or simply has no assets, the judgment may be unenforceable. This is the fundamental weakness of direct deposits: recovery after the fact is difficult even when the law is on your side.

If the builder was a TrustMark registered business, there may be a deposit protection scheme or insurance-backed guarantee that covers some or all of your loss. Always check trade body protections before starting court proceedings, as they are typically faster and less stressful.

Better protection against deposit loss is structural: using an escrow service where the funds never enter the builder's account in the first place. If the project does not proceed, the money stays held until you and the builder agree what happens to it, or a surveyor decides, rather than you chasing it through the courts.

Practical deposit checklist before you pay

Before transferring any deposit to a builder, run through this checklist. If the builder trades as a limited company, check it on Companies House and look at its filing history. Verify they carry public liability insurance (ask for the certificate, not just their word). Read at least ten independent reviews across Checkatrade, Google, and Houzz. Check their membership of a recognised trade body such as FMB, TrustMark, or BALI. Use the Renopay stage planner to structure the remaining payments as milestones.

If everything checks out and you are comfortable with the deposit amount, pay by bank transfer with a clear reference linking the payment to your contract. Keep a copy of the transfer confirmation alongside your contract. And ensure the remaining payments are structured as milestones, so that the deposit is the last unprotected payment you ever need to make on the project.

Frequently asked questions

Should I pay a builder a deposit upfront?

It is reasonable if the deposit is proportionate to the cost of the first stage’s materials and set out in a written contract. Once it reaches the builder’s account it is hard to recover, so you can also buy those materials yourself, or pay for each stage before it starts with the money held securely until the stage is approved.

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

Not for most UK renovation projects, where 10% to 15% of the contract value is a sensible ceiling. A deposit of 30% or more with no material-cost justification is a significant red flag. A higher deposit can be justified by genuine costs, such as bespoke joinery or structural steel with a long lead time, so ask for an itemised breakdown of materials, suppliers, unit costs and delivery dates before you agree.

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

You can ask to, and it makes sense when the deposit is mainly paying for bespoke or long-lead items such as structural glazing, handmade kitchen units or imported stone. The builder still gets the materials they need, you keep ownership of the goods until they are installed, and your money sits in a tangible asset on site rather than in the builder’s bank account.

Can I get my deposit back if my builder never starts work?

Under the Consumer Rights Act 2015, a builder who takes a deposit and fails to provide the agreed service is in breach of contract, so you are entitled to a remedy. Getting the money back is harder. If the builder is TrustMark registered, check for deposit protection or an insurance-backed guarantee first. Otherwise the small claims track handles claims up to £10,000, but a court judgment is not always enforceable.