In this article
A full VAT invoice must show a sequential unique number, the time of supply, the date of issue, your name, address and VAT number, the customer's name and address, a description of what was supplied, the quantity and VAT rate and net amount per line, the gross total excluding VAT, the rate of any cash discount, the total VAT in sterling, and the unit price. It must be issued within 30 days of the tax point.
The particulars are set out in law, not in guidance, and that's worth knowing, because the guidance summarises and the law governs.
The short version
- The required particulars are in regulation 14 of the VAT Regulations 1995.
- You have 30 days from the tax point to provide the invoice, unless HMRC has allowed longer by direction.
- Issue within 14 days of the basic tax point and the invoice date becomes the tax point. That rule is voluntary and you can opt out of it.
- A tax point created by the 14 day rule covers the whole value of the supply, not only the amount you invoiced.
- Less detailed invoices are for retailers, at £250 or less including VAT, with no exempt supplies. Not a general small-invoice allowance.
The short answer
If you and your customer are both VAT registered, the document you send has to carry the particulars in regulation 14. Your number has to be sequential and unique. Your VAT has to be shown separately and totalled in sterling. And it has to reach your customer within 30 days of the tax point.
What a full VAT invoice must show
Regulation 14(1) lists the particulars:
| Particular | Note |
|---|---|
| A sequential number based on one or more series which uniquely identifies the document | Sequential is the wording of the law, not a convention |
| The time of supply | The tax point. See below |
| The date of issue | Separate from the time of supply |
| Your name, address and VAT registration number | The registered name |
| The customer's name and address | |
| A description sufficient to identify the goods or services | "Consultancy" is thin. "Consultancy, 12 hours, July 2026" identifies it |
| For each description: the quantity, the rate of VAT and the amount payable excluding VAT | Per line, not per invoice |
| The gross total amount payable excluding VAT | |
| The rate of any cash discount offered | Only if you offer one |
| The total amount of VAT chargeable, in sterling | Sterling even where the invoice is in another currency |
| The unit price |
Three annotations apply only in specific cases, and your invoice has to carry them where they do: a margin scheme reference, a reverse charge reference, and a free zone reference.
Note that sub-paragraphs (f) and (k) of regulation 14(1) have been omitted by amendment, so if you find a list elsewhere with unbroken lettering, it's out of date. The safest thing is to read the current lettering off the legislation page instead of trusting a summary, including this one.
When you have to issue it
Within 30 days of the time when the supply is treated as taking place, or within such longer period as HMRC allows by general or specific direction (VATREC6010).
Those 30 days run from the tax point, not from the date you raise the document. That distinction matters when you finish work in one month and your invoice goes out in the next.
The tax point, and the 14 day rule
The tax point decides which VAT period a sale falls into, and it isn't automatically your invoice date.
There is a basic tax point, set by when the goods were removed or made available or the service was performed. Then there's a rule that overrides it. If you issue a VAT invoice within 14 days of the basic tax point, the date of your invoice becomes the tax point (VATTOS5235).
The rule is voluntary. You can opt out and keep the basic tax point, and at a quarter end that's occasionally what you want. Not everybody realises there's a choice being made here.
The tax point it creates covers more than the amount you invoiced. If you under-invoice a supply inside the 14 days, you've still created a tax point for the whole value of it, and the shortfall doesn't wait for a second invoice.
Miss the 14 days and the basic tax point stands, which is how VAT ends up in the wrong quarter.
Less detailed invoices are a retail provision
The most commonly misstated rule in UK invoicing is this one, because the £250 figure gets repeated without the condition attached to it.
Start with what the rule is for. A retailer only has to provide a VAT invoice when a customer who is a taxable person asks for one (regulation 16). It's a concession for businesses selling over a counter, so that a shop isn't writing out invoices for every sale.
When a customer does ask, and the supply including VAT is £250 or less, and the invoice includes no exempt supplies, the retailer can issue a less detailed invoice (VATREC16042). That form shows the retailer's name and address, the VAT number, the time of supply, a description of what was supplied, the VAT rate, and the gross amount payable at each rate.
The test is what your business is, not how small the sale is. If you're not a retailer, every VAT invoice you issue is a full one, so a consultancy invoicing £200 needs the complete set of particulars, and so does a practice invoicing £150.
VAT invoice failures to watch for
These five come up over and over:
- Broken numbering. The law says sequential, and if you restart per client or per year you produce duplicate numbers across your ledger, which is one of the main reasons a payment can't be matched back to an invoice automatically.
- A trading name where the registered name belongs. Your registered name has to appear.
- A description nobody can reconcile. One word plus an amount isn't a description sufficient to identify the supply, and it invites a query instead of a payment.
- VAT shown as a lump. The rate and net amount belong on each line, with the total VAT in sterling.
- Treating a small invoice as exempt from the detail. The full set of particulars applies to you unless you're a retailer.
Common questions
What must a full VAT invoice show? A sequential unique number, the time of supply, the date of issue, your name and address and VAT registration number, the customer's name and address, a description sufficient to identify what was supplied, the quantity and VAT rate and net amount for each line, the gross total excluding VAT, the rate of any cash discount, the total VAT in sterling, and the unit price. Margin scheme, reverse charge and free zone references apply where relevant.
How long do I have to issue a VAT invoice? Thirty days from the time the supply is treated as taking place, unless HMRC has allowed you longer by direction.
Does the invoice number have to be sequential? Yes. Regulation 14 requires a sequential number based on one or more series which uniquely identifies the document. More than one series is allowed, so a per-entity or per-branch series is fine as long as numbers are unique and sequential within it.
What is the 14 day rule? If you issue a VAT invoice within 14 days of the basic tax point, the invoice date becomes the tax point. The rule is voluntary and you can opt out of it. A tax point created this way covers the whole value of the supply, not only the amount invoiced.
Can I issue a simplified VAT invoice for a small amount? Only if your business is a retailer. A retailer need not issue a VAT invoice unless a VAT-registered customer asks for one, and can then use the less detailed form where the supply including VAT is £250 or less and the invoice includes no exempt supplies. The test is what your business is, not how small the sale is, so every other business issues a full VAT invoice whatever the amount.
Does the VAT have to be in sterling? Yes. The total VAT chargeable must be shown in sterling even where the rest of the invoice is in another currency.
Sources
- legislation.gov.uk — VAT Regulations 1995, regulation 14 (accurate as of August 2026)
- legislation.gov.uk — VAT Regulations 1995, regulation 16 (accurate as of August 2026)
- HMRC — VAT Time of Supply manual, VATTOS5235 (accurate as of August 2026)
- HMRC — VAT Trader Records manual, VATREC6010 (accurate as of August 2026)
- HMRC — VAT Trader Records manual, VATREC16042 (accurate as of August 2026)
Reviewed by the Adfin team. This article explains what VAT invoices must show and is not tax advice. VAT requirements are correct as of August 2026; check current HMRC guidance and the legislation before relying on them. Last updated August 2026.
