What must be on a UK invoice
Every invoice needs a unique number, your business name and address, your customer's name and address, the invoice date, the date you supplied the goods or work, a clear description of what you're charging for, and the total to pay. A limited company must use its full registered name. GOV.UK lists it all on invoices: what they must include.
If you're VAT registered
A VAT invoice needs more. As well as the basics, it must show:
- your VAT registration number
- a number that follows on from your last invoice
- the tax point (time of supply), if it isn't the invoice date
- the quantity, unit price and VAT rate for each line
- the total before VAT, the VAT at each rate, and the total VAT
You can invoice in euros or dollars, but the total VAT must also be shown in pounds sterling. Zero-rated and exempt lines both carry no VAT, but they aren't the same thing, so the invoice shows them separately.
If you're not VAT registered
Don't add VAT and don't call it a VAT invoice. Just call it an invoice. You must register for VAT once your taxable turnover goes over the threshold, which is £90,000 in any rolling 12 months at the time of writing. It can change, so check the current threshold on GOV.UK.
How the VAT is worked out
Each line is quantity × unit price, rounded to the penny. The VAT is then worked out once for each rate, on the total of the lines at that rate, and rounded to the nearest penny. HMRC's rules on rounding are in the VAT guide (Notice 700). Whichever way you round, do it the same way every time.
This tool helps you lay out an invoice. It isn't tax advice. If you're not sure which VAT rate applies, check VAT rates on different goods and services on GOV.UK or ask an accountant.