How to Chase Unpaid Invoices as a Plumber

Plumbers are particularly exposed to late and disputed payment for a few structural reasons. First, the work often happens inside people's homes during a disruption — a bathroom refurb, a new boiler, an emergency leak. Customers can confuse "the job was stressful" with "the job wasn't done right" when the invoice arrives, and use perceived dissatisfaction as a reason to delay payment.

Second, plumbers often work in landlord-to-tenant property chains. The landlord authorises the work, the tenant is present, and the managing agent holds the budget — and the invoice can bounce between all three before anyone pays it.

Third, emergency callouts present a specific risk. A customer in a panic about a burst pipe agrees to whatever is necessary to get it fixed. Once the emergency has passed and the stress has gone, the invoice can feel like a shock — and some customers push back.

None of this makes late payment acceptable. You have legal rights to recover what you're owed, with interest, if necessary. The first step is having a clear system that you follow every time.

A structured sequence means you always know what to do next and you have a paper trail if the debt escalates. Run this on every overdue invoice, without exception.

Stage 1 — Friendly reminder (7 days after due date)

Most invoices at this stage are simply forgotten or lost in a cluttered inbox. A short, friendly message — not apologetic, just practical — is all that's needed. Don't compound the awkwardness by apologising for chasing money that's legitimately owed to you.

Stage 2 — Firmer reminder (14 days after due date)

Two weeks overdue. Your tone should now be clear that you expect prompt payment. Reference the invoice number and original due date explicitly. A phone call at this stage, combined with an email, is often more effective than a message alone.

Stage 3 — Formal notice (30 days after due date)

This is a formal written notice that the invoice is significantly overdue. State the amount, the due date, and give a deadline (7 days) for payment. Notify the debtor that statutory interest will be applied if this is a business-to-business debt, or that contractual interest will apply if your terms include it for consumer debts.

Stage 4 — Final warning with interest applied (45 days after due date)

Your last step before formal recovery. State the updated total including statutory interest and compensation (for B2B debts), give a final 7-day deadline, and state clearly what legal action you will take if payment is not received.

Between stages, call. A direct conversation is harder to ignore than a message. Keep records of every call — date, time, who you spoke to, what was said. This documentation matters if the case ever goes to court.

The Late Payment of Commercial Debts (Interest) Act 1998 is the key piece of UK legislation protecting tradespeople from non-payment by business clients. It gives you the automatic right to charge interest on overdue business-to-business invoices — even if your original contract didn't mention it.

The Act entitles you to:

• Statutory interest at 8% above the Bank of England base rate, calculated daily from the date payment was due
• Fixed compensation: £40 automatically added for debts under £1,000; £70 for debts between £1,000 and £9,999; £100 for debts of £10,000 or more
• Reasonable recovery costs: if your actual costs (for example, a solicitor's fee) exceed the fixed compensation, you can claim the difference

The Act applies when both parties are acting in the course of a business — so it covers work for landlords, letting agents, property management companies, small building contractors, and any other commercial client. It does not apply to private consumer transactions, though you can include equivalent contractual terms in your quotes and terms of business.

For landlord and property management chains specifically: the Act applies based on who you contracted with, not who lives in the property. If you contracted with a landlord or their agent, it's a B2B transaction. Get this confirmed in writing before the job starts — a simple email exchange confirming the job and who is paying is sufficient.

Small claims court is available to any business or individual with a debt dispute under £10,000. The process is entirely online through the GOV.UK Money Claims service, and you don't need a solicitor.

The process

1. Before filing, send a "letter before claim" — a formal final warning that you intend to sue if payment isn't received within 14 days. This is a pre-action protocol requirement and also your last chance to prompt payment without court involvement
2. File your claim at gov.uk/make-court-claim-for-money. You'll need: the debtor's name and address, the amount owed (including interest if applicable), and a short description of the dispute
3. Pay the court fee, which is scaled by claim size. For example: claims up to £300 cost £35; £300–£500 costs £50; £500–£1,000 costs £70; £1,000–£1,500 costs £80; £1,500–£3,000 costs £115; £3,000–£5,000 costs £205; £5,000–£10,000 costs 5% of the claim. These fees are recoverable if you win
4. The defendant has 14 days to respond. No response means you can apply for a default judgment automatically
5. If they contest the claim, a hearing will be scheduled. Small claims hearings are informal. Bring your invoice, any written agreement (quote, email chain), photos of completed work, and every piece of correspondence from your chase sequence

Plumbing-specific documentation tips

For bathroom installations and larger jobs, take photos on completion. Get a written sign-off or at minimum an email from the customer acknowledging the work is done. For emergency callouts, note the date, time, customer name, property address, fault description, and work carried out. This contemporaneous evidence is decisive in disputed claims.

When your own chasing has stalled, you have three main escalation options. Choose based on debt size, age, and how disputed the amount is.

Debt collection agency

No upfront cost — agencies work on a contingency, typically taking 10–25% of recovered funds. They add the external pressure of a third-party demand. Useful for smaller or older debts where court action isn't commercially worthwhile for you. The downside: a significant share of the recovery goes to the agency, and some debtors ignore collection agencies just as they ignore you.

Solicitor's letter before action

A letter on a solicitor's letterhead dramatically changes the dynamic for most debtors. Many simply pay to avoid legal proceedings. Fixed-fee debt recovery letters are available from many solicitors for £30–£75. For debts of a few hundred pounds, this is often the most cost-effective single step you can take after your own chasing has failed.

Small claims court

The strongest option for undisputed debts under £10,000. Suitable when you have good documentation, the debt is undisputed in principle (the customer acknowledges the work was done but simply won't pay), and you're prepared to attend a short hearing if necessary. Court fees are recoverable, and a county court judgment (CCJ) has serious consequences for the debtor's credit record — which makes the threat of filing credible.

For landlord and property management non-payment specifically: escalate faster than you would for domestic clients. These entities understand legal processes and often don't pay until they have to.

Adapt these for your own use — keep your own voice, but include all the factual detail shown.

Stage 1 — Day 7, friendly reminder

Subject: Invoice [INVOICE NUMBER] — Just a Quick Reminder

Hi [NAME], just a quick note — invoice [INVOICE NUMBER] for [AMOUNT] was due on [DATE]. Could you arrange payment when you get a chance? Bank transfer: [SORT CODE / ACCOUNT NUMBER], ref [INVOICE NUMBER]. Let me know if you have any questions. Thanks, [YOUR NAME].

Stage 2 — Day 14, firmer reminder

Subject: Invoice [INVOICE NUMBER] — Payment Overdue

Hi [NAME], I'm following up on invoice [INVOICE NUMBER] for [AMOUNT] (due [DATE]), which remains unpaid. Please arrange payment as a priority. If there's a problem with the invoice, please contact me straight away. Bank transfer: [SORT CODE / ACCOUNT NUMBER], ref [INVOICE NUMBER]. [YOUR NAME].

Stage 3 — Day 30, formal notice

Subject: Invoice [INVOICE NUMBER] — Formal Notice of Overdue Payment

Dear [NAME], Invoice [INVOICE NUMBER] for [AMOUNT], due on [DATE], remains unpaid [X] days after the due date. This is formal notice that payment is required within 7 days. If this is a business account, statutory interest will be applied from the due date in accordance with the Late Payment of Commercial Debts (Interest) Act 1998 if payment is not received. [YOUR NAME].

Stage 4 — Day 45, final warning

Subject: Invoice [INVOICE NUMBER] — Final Notice Before Legal Action

Dear [NAME], Invoice [INVOICE NUMBER] for [AMOUNT] (due [DATE]) remains unpaid. Statutory interest of [CALCULATED INTEREST] and fixed compensation of [£40/£70/£100] have now been added under the Late Payment of Commercial Debts (Interest) Act 1998, bringing the total to [NEW TOTAL]. Payment must be received by [DATE — 7 days from now]. If payment is not received, I will issue a claim through the County Court without further notice. [YOUR NAME].

The most efficient way to manage late payment is to reduce how often it happens. These practices make a material difference:

• Deposits on all jobs over £500: A 25–50% upfront deposit covers materials and qualifies the customer. It's also a practical test — a customer who refuses a deposit on a large bathroom installation is a higher credit risk
• Short payment terms: 7 days for domestic work. 14 days maximum for commercial clients. "30 days net" is for large contractors with established credit relationships — not for a one-off bathroom job with a private customer
• Invoice on completion, not days later: Send the invoice the moment the job is done — ideally before you leave. The longer you wait, the easier it is for payment to drift down the customer's priority list
• State terms clearly in your quote: "Payment due within 7 days of completion. A deposit of [X]% is required before work commences." Written terms reduce disputes and create a clear contractual baseline
• Offer on-site payment: A card reader (SumUp, Square, or Zettle) lets you collect payment on the day. Most domestic customers are happy to pay immediately — they just need the option to be offered
• For landlord chains, invoice the right person: Establish before you start who is authorising the payment — landlord, agent, or the company that owns the property. Send the invoice directly to the payment decision maker, not to whoever happened to book the job