United Kingdom VAT number format
By Jose PollmanPublished Updated
The shape
A number written in full begins GB, then:
- 9 digits
Format examples
Both show the shape only. Neither is a real registration, and neither will resolve to a company.
GB123456789GB987654321
The pattern
This is the regular expression this site applies, after the prefix has been stripped. It is the same expression the checker runs, not a description of it.
^(\d{9}|\d{12}|GD\d{3}|HA\d{3})$Where to verify it
VIES does not answer for Great Britain: GB numbers left the EU VAT system with Brexit. HMRC has its own checker, and this site verifies the official check digit locally instead — which proves a number cannot exist if it fails, but never that it is registered.
What people get wrong
- The country code goes at the beginning, never the end, and it is part of the number: GB first, then the digits. Invoices print it both ways and some systems store it without the prefix, so if a check fails, try it with and without.
- This site cannot look the registration up: HMRC requires an approved application for its VAT API. The official check digit is verified locally instead, which proves a number is not mistyped or invented — never that it is registered, or to whom.
- Group and branch registrations use a longer form, so an unusually long number is not automatically wrong.
Run a vendor check →Registry, IBAN, EU sanctions and sending domain, in one pass. Free, no signup.
Invoice Checker →Drop in a supplier’s invoice, or paste its text, and the VAT numbers, bank accounts and email domains on it are read out in your browser — the file itself is never uploaded. Correct anything misread, then run every check at once.