What to put on an invoice (UK), and how to get it paid on time

An invoice does two jobs: it is the legal record of a sale, and it is the document that gets you paid. Most invoices do the first job and neglect the second. This guide covers what has to be on it and what makes it get paid. General information, not legal or tax advice; the detail is on gov.uk.

What every UK invoice must show

Whether or not you are VAT registered, an invoice should include:

• The word Invoice, and a unique, sequential invoice number
• Your business name, address and contact details. A sole trader must show their own name and any business name they trade under; a limited company must show its full registered name and, if it shows directors' names, all of them
• The customer's name and address
• The date of the invoice
• A clear description of what was supplied, and when
• The amount for each item, and the total
• How and when to pay: bank details, the due date, any reference to quote

If you are VAT registered, you also need

A VAT invoice must add:

• Your VAT registration number
• The tax point (time of supply), if it differs from the invoice date
• For each line, the rate of VAT and the net amount
• The total VAT and the total including VAT, in sterling
• Any discount offered for prompt payment

For sales under £250 including VAT to consumers you can issue a simplified VAT invoice with less detail, but the full version is never wrong. If you are not registered, do not show VAT anywhere; a line saying "no VAT to add" avoids questions.

Numbering

Sequential and unique, with no gaps. A cancelled invoice is not deleted: raise a credit note against it. A simple scheme is a year prefix and a counter, such as 2026-041, which also makes finding things in a year's time easier.

Payment terms that get you paid

The terms belong on the quote first, the invoice second. A customer who accepted a quote saying "deposit on booking, balance within 7 days of completion" has agreed to those terms; one who first sees them on the invoice has not.

Some things that help, from most to least effective:

1. Invoice immediately. The day the job finishes, or the moment the milestone is reached. Every day of delay in sending is a day of delay in paying.
2. Short terms. Seven or fourteen days is normal for small trade and service businesses. Thirty days is a convention inherited from large companies, and you do not have to adopt it.
3. A specific due date, not "net 14". Write "Due by 8 October 2026".
4. Make paying easy. Bank details on the invoice; a payment link if you have one; no "please ring for our account details".
5. Deposits for anything with materials or more than a few days' work.
6. Send it to the person who pays, which in a larger customer is often not the person who ordered.

If no terms were agreed at all, the law implies 30 days for business-to-business sales.

When it is late

The late payment rules give businesses the right to charge statutory interest on overdue business-to-business invoices at 8% above the Bank of England base rate, plus a fixed compensation amount per invoice (£40, £70 or £100 depending on the size of the debt). You do not have to charge it, but knowing you can changes the tone of the conversation, and many businesses mention it on the invoice.

A practical sequence that recovers most late invoices without damaging the relationship:

Log every contact with its date. If it ever goes to a claim, the record of your reminders is your evidence.

Keep the paperwork together

Keep the quote, the acceptance, the invoice and the payment record for each job, and keep them for at least six years. It sounds bureaucratic for a small job; it is a ten-second habit that has ended a great many arguments.