Should my Gas Safe number go on the invoice?

Put it on if the job was gas work. The customer may need it for a landlord certificate, a house sale or their own records, and an invoice carrying the number is one they keep rather than bin. It also quietly answers the question they were too polite to ask.

How do I invoice an emergency callout fairly?

Split the callout, the parts and the time into separate lines rather than sending one figure. Somebody who has just watched water come through a ceiling is grateful on the night and analytical by the weekend, and a single number is what turns the second feeling into a phone call. Three lines show what they actually bought.

Do my invoice numbers have to be sequential?

They should be unique and consistent. 001, 002, 003 is the easy convention, and it's what makes 'invoice 032' unambiguous on the phone and at tax time. Don't reuse or duplicate numbers; gaps are fine.

When should I send the invoice?

The day the job finishes, from the van ideally. An invoice sent three weeks late quietly tells the customer that paying it late is fine too, and it's the single most fixable cause of slow payment.

Free plumber invoice template

A free invoice template for plumbers, visible in full below, downloadable as a PDF, no signup asked. It is laid out the way plumbing work actually gets billed: the call-out as its own line, parts separated from labour, and room for a Gas Safe number where a customer or a landlord will go looking for it. Fill it in, send it the day the job finishes, and it reads like a business rather than a favour that can wait.

Free PDF · fills in by hand or in any PDF app · no signup

Tired of retyping templates? SoloDesks builds and sends invoices from your phone on the free plan, in about 60 seconds per invoice.

INVOICE

Your Business Name

Phone · Email

Address

Invoice no.

Date

Due date

Description	Qty	Price
Call-out & diagnosis
Labour: leak repair (2 hrs)
Parts: 15mm copper pipe & fittings
Replace basin tap (supplied & fitted)
Waste removal & disposal
Add your own lines…

Subtotal

VAT (if registered)

TOTAL

Payment details & terms

What a plumber's invoice must include

Your business name and contact details (and logo, if you have one)
A unique invoice number, where sequential is fine, gaps are fine, duplicates are not
Invoice date and payment due date
The client's name and the job address
Itemised lines: each piece of work and each material, with its price
The total, and whether VAT (or your local sales tax) is included
How to pay: bank details or a payment link
Payment terms, because "due within 7 days" is a term; silence is a suggestion
Your Gas Safe registration number, where the job was gas work

Tips from the trade

Separate parts from labour. A cylinder and four hours are not one number, and itemising is what stops the haggling.
Name the parts. "Parts: pump, TRV ×3" reads as checkable; "materials" reads as padding.
Charge the call-out as its own line so diagnosis is visibly paid work, not free.
For emergency jobs, invoice the same day. The 7pm burst pipe is the job most likely to never get billed.

Common questions

Should my Gas Safe number go on the invoice?: Put it on if the job was gas work. The customer may need it for a landlord certificate, a house sale or their own records, and an invoice carrying the number is one they keep rather than bin. It also quietly answers the question they were too polite to ask.
How do I invoice an emergency callout fairly?: Split the callout, the parts and the time into separate lines rather than sending one figure. Somebody who has just watched water come through a ceiling is grateful on the night and analytical by the weekend, and a single number is what turns the second feeling into a phone call. Three lines show what they actually bought.
Do my invoice numbers have to be sequential?: They should be unique and consistent. 001, 002, 003 is the easy convention, and it's what makes 'invoice 032' unambiguous on the phone and at tax time. Don't reuse or duplicate numbers; gaps are fine.
When should I send the invoice?: The day the job finishes, from the van ideally. An invoice sent three weeks late quietly tells the customer that paying it late is fine too, and it's the single most fixable cause of slow payment.

Quoting the job before you bill it? Plumber's quote template is the other half of the same paperwork, written for the same trade. Not a plumber? The blank UK invoice template works for any trade, in Word, Excel, PDF or Google Docs.

The same invoice for other trades

Or never fill in a template again

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