What to put on an invoice in the UK

An invoice is a request for payment, and it's also a record. Get the details right and you're paid faster, your client's accounts team doesn't come back with questions, and your own books add up at the end of the year.

Here's what the law and HMRC expect on a UK invoice, in plain English.

Every invoice needs

• A unique invoice number. Number them in order (INV-0001, INV-0002…) and don't skip or reuse numbers. If you need to correct an invoice, cancel it and issue a new one rather than editing the old one.
• Your details. If you're a sole trader, your name and any business name you trade under, plus an address where legal documents can be delivered to you.
• Your customer's details. Their name, or their company name, and address.
• What you're charging for. A clear description of the work or goods, not just "services".
• The date of the invoice, and the date the work was done or the goods were supplied, if that's different.
• The amounts. What each item costs and the total owed.

It's also sensible to add how to pay (your bank account name, sort code and account number) and when payment is due. There's no legal rule on payment terms between businesses, but if you don't agree a date, a business payment counts as late 30 days after the customer receives your invoice. Writing "Payment due within 14 days" removes any doubt.

If you're a limited company

Use the company's full name exactly as it appears on its certificate of incorporation. If you list any directors' names on the invoice, you have to list all of them.

If you're registered for VAT

VAT invoices need extra details, including your VAT registration number, the tax point (time of supply), the VAT rate for each item and the amount of VAT charged. HMRC's guidance on VAT invoices sets out the full list, and there are simpler rules for small retail sales. If you're not VAT registered, don't charge VAT and don't show a VAT number.

How long to keep your copies

As a sole trader, keep your business records, invoices included, for at least five years after the 31 January Self Assessment deadline for that tax year. Limited companies generally keep records for six years. A copy on your phone counts, as long as you can produce it if HMRC asks.

A quick checklist

1. Unique, sequential number
2. Your name (and trading name) and address
3. Customer's name and address
4. Clear description of the work
5. Invoice date, and supply date if different
6. Amounts and total
7. How and when to pay
8. VAT details, only if you're VAT registered

Why I built this into an app

Most of the tradespeople I spoke to weren't worried about writing an invoice. They were worried about getting one detail wrong, losing track of what was sent, or editing an old invoice and making a mess of their records. So Thistle Invoice numbers invoices in sequence for you, never lets a sent invoice be quietly changed (corrections void the original and issue a new one), and fills in your details on every PDF.

This guide is general information, not tax advice. If your situation is complicated, a quick chat with an accountant is worth it.