If your UK business is VAT-registered, your invoices have to do more than ask for payment — they are legal tax documents, and HMRC is specific about what must be on them. Get it wrong and your customer cannot reclaim the VAT, which is a fast way to lose repeat business.

Here is what a compliant UK VAT invoice needs.

The essentials every VAT invoice must show

  • Your business name, address and VAT number — the VAT number is the part people most often forget.
  • A unique invoice number — sequential, with no gaps or duplicates.
  • The invoice date and the tax point (the date the goods or services were supplied, if different).
  • Your customer's name and address.
  • A description of the goods or services, with quantities.
  • The VAT rate applied to each item — standard 20%, reduced 5%, zero-rated 0%, or exempt.
  • The VAT amount per rate, and the total excluding VAT, the VAT, and the total including VAT.
  • The total amount payable and the currency.

For a full checklist and examples, see the guide: UK VAT Invoice Requirements.

Full VAT invoice vs. simplified invoice

For supplies under £250 (including VAT), a simplified VAT invoice is allowed — it needs your name, address and VAT number, the date, a description, and the VAT rate and amount. Anything above that, or any invoice where the customer needs to reclaim VAT, should be a full VAT invoice with everything listed above.

Common mistakes

  • Missing or wrong VAT number. Without it, the invoice is not a valid VAT invoice.
  • One VAT figure for mixed rates. If you sell items at different rates, show the VAT separately for each rate.
  • No tax point date. If you issue the invoice after the supply date, state both dates.
  • Rounding errors. The VAT shown must add up to the total; even a penny out can cause a query.

Making compliant invoices without the hassle

You do not need accounting software to get the format right. A free tool such as NexBillio — a free online invoice generator, no sign-up needed — lets you enter your business details and VAT number, add line items with their tax rates, and download a professional PDF in seconds. It also covers quotes, estimates, receipts, proforma invoices and credit notes.

A VAT invoice is a small document with outsized consequences. Get the required fields right once, save a template, and every invoice after that takes a minute.