Customer Won't Pay? How Tradespeople Can Protect Themselves Before the Job Starts

Every trade has been there. You finish a job, the customer seems happy, and then the invoice goes unpaid. You chase, you wait, you chase again — and meanwhile your business is carrying the cost. It is one of the most stressful situations a tradesperson faces, and the worst part is that most of it can be prevented before you even pick up a tool.

This is not about what to do when someone already owes you money. This is about setting things up so you never end up in that position in the first place. Prevention beats recovery every time.

Why verbal agreements are a gamble you cannot afford

Verbal agreements are legally binding in the UK. The Consumer Rights Act 2015 applies whether or not you have something in writing. The problem is not legality — it is proof.

A customer can agree to a price, a scope, and a payment schedule over the phone. Six weeks later, they can claim they never agreed to any of it. Without a written record, you have no evidence. It becomes your word against theirs, and in court, that is an argument you will struggle to win.

Every trade forum has stories of tradespeople losing thousands because nothing was in writing. One plumber described finishing a £4,000 bathroom refit, only for the homeowner to claim they had agreed "around £2,500" and refuse to pay more. No contract, no texts, no proof — the plumber walked away with half what they were owed.

Verbal agreements fail because memories are unreliable. What you remember agreeing and what the customer remembers are often completely different. A written contract means both sides are looking at the same thing six months later.

The legal position: contracts vs verbal agreements

Under English common law, a contract does not have to be written to be enforceable. A verbal agreement that includes offer, acceptance, and consideration (something of value exchanged) is technically binding.

The Consumer Rights Act 2015 applies to all services provided to consumers, written or verbal. It requires that work is carried out with reasonable care and skill, within a reasonable time, and for a reasonable price if none was agreed. These protections exist regardless of whether you have a contract.

But here is the problem: proving what was agreed is nearly impossible without documentation. If a dispute goes to court, the judge needs to see evidence. Invoices, quotes, text messages, emails — these all help. But a signed contract that clearly sets out the terms is the strongest evidence you can have.

Stage payments: the single best way to protect your cash flow

Even with a written contract, asking for payment in full on completion is a risk. If the customer disputes the final bill, you are chasing the entire amount. A better approach is stage payments tied to milestones.

For example:

• 30% deposit on signing
• 30% when first fix is complete
• 30% when second fix is complete
• 10% retention on final completion and sign-off

This structure means you are never more than one stage ahead financially. If a customer refuses to pay at any point, you can stop work without having done thousands of pounds of unpaid labour. It also builds trust — the customer sees that you are not asking for all the money upfront.

Stage payments are standard in commercial construction for exactly this reason. They protect both sides and keep the project moving. For a detailed breakdown of fair percentages at each stage, see our stage payment guide for UK extensions.

Handling deposits

A deposit is not about distrust. It is about commitment. When a customer pays a deposit, they are confirming that they are serious about the project. When you accept a deposit, you are confirming that you have reserved time in your diary for their job.

A reasonable deposit for domestic work is typically 10% to 30%, depending on the size of the project and material costs. If you need to order expensive materials upfront — a bespoke kitchen, specialist tiles, structural steel — a higher deposit is justified. Be transparent about why: "I need a 25% deposit because the materials alone cost £3,000 and I need to order them before I can start."

Avoid asking for more than 50% upfront. Large upfront payments create nervousness, and if a customer has already paid most of the bill before work starts, you lose the leverage that stage payments give you. The point is to keep both sides invested at every phase of the project.

What if the customer does not want to pay a deposit?

If a customer refuses to pay any deposit at all, that is a warning sign. It may mean they are not serious, or it may mean they have been burned before and do not trust the process. In either case, the solution is the same: a clear contract that explains how the payment structure works and why it protects both sides.

A professional contract with a sensible deposit and stage payments is something any reasonable customer will accept. If they will not, you need to decide whether the risk of doing the job without that protection is worth it. More often than not, it is not.

Why a signed contract is the most powerful debt prevention tool

A signed contract does several things that a verbal agreement or even a written quote cannot do:

• It proves what was agreed. No arguments, no misremembering. The terms are written down and both sides signed it.
• It sets expectations upfront. The customer knows what they are getting, what it costs, and when payments are due. Most disputes come from mismatched expectations — a contract prevents that.
• It gives you a clear legal position. If you need to send a formal demand or go to court, you have a document that shows exactly what the customer agreed to. Courts take written contracts seriously.
• It makes you look professional. Homeowners are more likely to trust — and pay — a tradesperson who operates like a business rather than someone who does everything on a handshake.

What to include in your contract

A contract does not need to be complicated. The best ones are short, clear, and cover the essentials. At minimum, include:

• Scope of works — a clear description of what you will do (and what you will not do)
• Price — the total cost, whether VAT is included, and how the price can change if the scope changes
• Payment terms — when payments are due, how much at each stage, and what happens if payment is late
• Timescales — start date, expected completion date, and what happens if there are delays
• Change process — how variations and extras are agreed and priced

Generic templates can be a starting point, but they often miss job-specific details or include irrelevant clauses. The best approach is a contract tailored to the specific project while covering the key terms.

Late payment terms: making non-payment expensive

If you include late payment terms in your contract, you can charge interest on overdue invoices. For B2B work (e.g., subcontracting to a main contractor), the Late Payment of Commercial Debts (Interest) Act 1998 gives you a statutory right to charge 8% plus the Bank of England base rate — currently a significant amount.

For consumer work (tradespeople directly to homeowners), the right to charge interest comes from your contract terms. A clause that says "invoices not paid within 14 days will incur interest at 2% per month" makes late payment expensive for the customer and gives you leverage.

Most customers pay on time when they know late payment has consequences. A clear contract with late payment terms removes any ambiguity.

Red flags: when to walk away before starting

Not every job is worth taking. Experienced tradespeople learn to spot the warning signs early — before they have committed time and money to a project that ends in a payment dispute.

Watch out for:

• Reluctance to put anything in writing. A customer who resists signing a contract is telling you something. If they will not agree to terms before work starts, they are unlikely to honour them after.
• Stories about previous builders. "The last three builders were all terrible." Sometimes the customer is the common factor. Ask what went wrong and listen carefully to the answer.
• Pressure to start immediately. Urgency is sometimes genuine, but it can also be a tactic to get you working before terms are agreed. A customer who respects your time will give you time to prepare a contract.
• Haggling after the quote. Negotiation is normal. But a customer who accepts your quote and then tries to renegotiate once you have started is showing you how they handle agreements.

None of these are guarantees of trouble, and some perfectly good customers tick one or two of these boxes. But if a potential client is refusing a deposit, refusing a contract, and telling you horror stories about their last builder — trust your instincts and walk away. The job you decline is sometimes the most profitable decision you make.

What to do if you are already in a non-payment situation

If you are reading this because someone already owes you money, the steps are:

1. Send a polite reminder — many late payments are just oversights
2. Send a formal written reminder — email is fine, but keep a record
3. Send a letter before action — this is the legal step before court proceedings. It must clearly state the amount, the terms, and a final deadline (usually 14 days). Courts expect to see one before you make a claim. For a practical template and guide, see our article on how to write a dispute letter.
4. Consider small claims court — for amounts up to £10,000, you can make a claim online without needing a solicitor

But the reality is that chasing unpaid invoices is stressful, time-consuming, and often costs more than the money you recover. Prevention is always better. If the situation is more serious — the customer has stopped communicating entirely, or you are considering leaving the job — see our guide on what happens when a builder walks off site, which covers both sides of that scenario.

The bottom line

You do not need to accept non-payment as an occupational hazard. A signed contract with clear payment terms, stage payments, and a professional approach puts you in control before the job even starts. It takes less time than writing a detailed quote — and it can save you thousands in lost income and legal fees.

Stop chasing money. Start every job with a signed TradeContract — it takes less time than writing a quote. Try it free.