What must a plumber include on an invoice?

A plumber's invoice must include your business name and contact details, the customer's name and address, a unique invoice number, the invoice date and payment due date, an itemised description of the work completed and materials used, the total amount due, your payment details (bank account or other methods), and your VAT number if VAT registered.

Do plumbers need to charge VAT on invoices?

You only need to charge VAT if your business turnover exceeds the VAT registration threshold, which is ninety thousand pounds per year as of 2026. If you are not VAT registered, you should not charge VAT but may want to state 'Not VAT registered' on your invoices to avoid confusion.

How should a plumber number their invoices?

Use a sequential numbering system that makes it easy to track and reference invoices. A common format is a prefix followed by a number, such as INV-001, INV-002, and so on. Some plumbers include the year, such as INV-2026-001. The key requirement is that each number is unique and sequential.

When should a plumber send an invoice?

Send your invoice the same day you complete the work, or at most the following morning. The longer you wait, the longer you wait to be paid. For larger jobs with agreed stage payments, invoice at each milestone as soon as it is reached.

How long should a plumber give customers to pay an invoice?

For residential plumbing work, payment on completion or within seven days is standard. For commercial work, fourteen to thirty days is common. Whatever terms you set, state them clearly on the invoice and ideally agree them with the customer before you start the work.

Free Plumber Invoice Template — What to Include & Examples

Getting paid promptly starts with a professional invoice. Yet many plumbers still scribble a total on the back of a business card or send a text message saying "That's two-fifty please." It works some of the time, but it leads to confusion, delayed payments, and a complete lack of records come tax return season.

A proper invoice takes just a few minutes to prepare and makes a significant difference to how quickly you get paid, how professional you appear, and how easily you can manage your bookkeeping. This guide covers everything a plumber needs to know about invoicing — what to include, the legal requirements, a practical example, and how to streamline the process.

What to Include on a Plumbing Invoice

A good plumbing invoice is clear, comprehensive, and easy for the customer to understand. Here is everything it should contain.

Your Business Details

At the top of the invoice, include your full business name (or your name if you trade as a sole trader), your trading address, phone number, and email address. If you are registered with a professional body such as CIPHE (Chartered Institute of Plumbing and Heating Engineering) or the Association of Plumbing and Heating Contractors, include your membership number. If you are Gas Safe registered, include your Gas Safe registration number — this reassures the customer and is a legal requirement for gas work.

Customer Details

Include the customer's name and the address where the work was carried out. If the billing address is different from the job address, include both. Getting this right matters for your records and theirs.

Invoice Number

Every invoice must have a unique sequential number. This is a legal requirement for record keeping and is essential for tracking payments. Use a simple system: INV-001, INV-002, INV-003, and so on. Some plumbers prefer to include the year (INV-2026-001) which makes it easier to organise records by tax year.

Dates

Include the date the invoice was issued, the date the work was carried out (if different), and the payment due date. For example: "Invoice Date: 27 February 2026. Work Completed: 26 February 2026. Payment Due: 6 March 2026." This leaves no ambiguity about when payment is expected.

Itemised Description of Work

This is the most important part of the invoice. Break down exactly what you did, listing each task as a separate line item. Be specific — "Replaced thermostatic mixing valve in main bathroom" is far better than "Plumbing work." Include the time spent on each task if you are charging by the hour, or simply describe the work if charging a fixed price.

For materials, list each item separately with its cost. This transparency builds trust and makes it clear that your prices are fair. Customers are far less likely to question a total when they can see exactly what was used.

Call-out or Attendance Fee

If you charge a call-out fee, list it as a separate line item. Many plumbers charge thirty to sixty pounds for a call-out, which covers travel time and the minimum attendance. Make sure the customer was aware of this charge before you attended — springing it on them after the event causes frustration and damages your reputation.

Costs and Totals

Show the subtotal for labour, the subtotal for materials, any call-out fee, and the overall total. If you are VAT registered, show the net amount, the VAT amount (at the current rate of twenty per cent), and the gross total. If you are not VAT registered, show the total and note "Not VAT registered" to avoid any confusion.

Payment Details

Make it as easy as possible for the customer to pay you. Include your bank name, account name, sort code, and account number for bank transfers. If you accept other payment methods — card payments, PayPal, or cash — list those too. The easier you make it to pay, the faster you get paid.

Payment Terms

State your payment terms clearly. For residential plumbing work, payment on completion or within seven days is standard. For commercial work, you may need to offer fourteen or thirty-day terms. Whatever your terms are, state them on the invoice and agree them with the customer before you start the work.

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Example Plumbing Invoice

Here is a practical example of what a well-structured plumbing invoice looks like. This is for a typical domestic job — an emergency call-out to fix a leaking pipe and replace a stop cock.

Header:

Jones Plumbing Services
12 Oak Lane, Leeds, LS1 4AB
Tel: 07XXX XXXXXX | Email: dave@jonesplumbing.co.uk
CIPHE Member No. 12345

Invoice To:
Mrs Sarah Thompson
48 Maple Avenue, Leeds, LS6 2CD

Invoice No: INV-2026-034
Invoice Date: 27 February 2026
Work Date: 27 February 2026
Payment Due: 6 March 2026

Description of Work:

Emergency call-out attendance fee — forty-five pounds
Diagnosed and repaired leak on 15mm copper pipe under kitchen sink (soldered joint repair) — one hour at forty-five pounds per hour = forty-five pounds
Replaced seized internal stop cock with new quarter-turn valve — one and a half hours at forty-five pounds per hour = sixty-seven pounds fifty pence

Materials:

15mm end feed coupling x2 — three pounds twenty pence
Lead-free solder and flux — two pounds fifty pence
22mm quarter-turn stop cock — eighteen pounds
22mm compression fittings x2 — seven pounds sixty pence
PTFE tape — one pound twenty pence

Subtotal (Labour): one hundred and fifty-seven pounds fifty pence
Subtotal (Materials): thirty-two pounds fifty pence
Total: one hundred and ninety pounds
VAT: Not VAT registered

Payment Details:
Bank: Lloyds Bank
Account Name: D Jones
Sort Code: XX-XX-XX
Account Number: XXXXXXXX

Payment Terms: Payment due within 7 days of invoice date. Bank transfer preferred.

Legal Requirements for Plumbing Invoices

HMRC requires all self-employed plumbers to keep accurate records of their income and expenses. Your invoices are a key part of this. While there is no specific legal format for invoices from non-VAT registered businesses, HMRC expects your records to show the date of each transaction, the amount, and what it was for.

VAT Invoices

If you are VAT registered (required once your turnover exceeds ninety thousand pounds per year), your invoices must include additional information: your VAT registration number, the tax point (usually the date of supply), the VAT rate applied, and a separate line showing the VAT amount. Failure to include these details can result in penalties from HMRC.

CIS Invoices

If you do subcontract work for other construction businesses, the Construction Industry Scheme (CIS) applies. Your invoice to the contractor should show the gross amount before CIS deduction. The contractor will deduct CIS tax (twenty per cent if you are registered, thirty per cent if you are not) and pay you the net amount. Keep records of all CIS deductions as you can offset them against your tax bill. For more on this, see our guide on CIS scheme explained for subcontractors.

Record Keeping

Keep copies of all invoices you send for at least six years — this is how long HMRC can look back in an investigation. Digital copies are perfectly acceptable and much easier to organise than paper. Save them in a folder structure by year and month, and back them up regularly.

Tips for Getting Paid Faster

Creating a good invoice is only half the battle. Here are practical tips to ensure you actually get paid promptly.

Invoice immediately. Send the invoice the same day you complete the work, or at the very latest the following morning. Every day you delay sending the invoice is a day added to when you get paid. If the job is finished at 3pm, send the invoice from your phone in the van before you drive to the next job.

Agree payment terms upfront. Before you start any job, confirm with the customer how and when you expect to be paid. This prevents awkward conversations later and sets clear expectations from the beginning.

Make payment easy. Offer bank transfer as the primary option and include your details on the invoice. Some plumbers also use payment links (through services like PayPal, Stripe, or SumUp) that let the customer pay with one click. The fewer steps between receiving the invoice and paying it, the faster you get your money.

Follow up promptly. If payment has not arrived by the due date, send a polite reminder the following day. Do not wait weeks hoping it will arrive. A quick text or email saying "Just a friendly reminder that invoice INV-2026-034 was due yesterday — could you let me know when the payment has been sent?" is perfectly professional and usually results in immediate payment.

Use staged payments on larger jobs. For bathroom installations, central heating system installations, or any job costing more than a few hundred pounds, structure payments in stages. A typical structure is a deposit of twenty per cent to secure the booking, a mid-point payment when the first fix is complete, and the balance on completion. This improves your cash flow and reduces the risk of non-payment on the full amount.

For a comprehensive guide on chasing overdue payments, see our article on how to deal with late-paying customers.

Digital Invoicing Tools for Plumbers

While a Word or Excel template works, digital tools make the process faster and more professional. Options for plumbers include:

Accounting software. QuickBooks, Xero, and FreeAgent all include invoicing features. These tools let you create and send invoices, track which ones have been paid, and automatically feed the data into your bookkeeping. They cost between twelve and thirty-five pounds per month.

Invoice apps. Dedicated apps like Invoice Ninja, Zoho Invoice, and Wave (which is free) let you create and send invoices from your phone. They are simpler than full accounting software but get the job done if invoicing is your main need.

QuoteSmith. If you want both quoting and invoicing in one place, QuoteSmith includes a free invoice generator alongside its AI-powered quoting system. You can create branded invoices in seconds and keep all your quotes and invoices in one place.