United Kingdom VAT number check

Q: Can I check VAT numbers from code or in bulk?

Yes. The same check is available over the REST API (GET /v1/gb/vat/{id}) and the MCP server, with the same key as every other country. See the API docs.

Check that a United Kingdom VAT number is well formed and its check digit is right, before you pay or onboard a supplier. Format only

Example: GB220430231 (Tesco). No account needed: 10 lookups a day per network, shared with the keyless API.

What this check tells you

Format only

We check the structure and the check digit published by the issuing authority, offline. That catches typos and made-up numbers. It does not show that the business exists, is registered or is active, so a well-formed number gets review, never pass. To confirm registration, use the official lookup: HMRC: check a UK VAT number.

United Kingdom ID formats we check

ID type	Level	Check digit	API endpoint	Official lookup
VAT VAT registration number	Format only	HMRC weighted mod 97 (including the 2010 “+55” series)	`GET /v1/gb/vat/{id}`	HMRC: check a UK VAT number
CRN Companies House company registration number	Format only	None published (structure only)	`GET /v1/gb/crn/{id}`	Companies House: find and update company information

From code

Same key and quota as every other country. A well-formed request costs one lookup; a source that does not answer returns HTTP 503 and is not counted.

curl "https://taxid.halpii.com/v1/gb/vat/GB220430231" \
  -H "Authorization: Bearer $KEY"

Get a no-cost API key (100 lookups a day) or read the API docs.

Questions

Does a valid VAT number mean the company exists?

No. This is a format check: it confirms the structure and check digit, not that the business exists or is active. Confirm registration with HMRC: check a UK VAT number.

Where does the data come from?

No registry is queried. The rules come from the issuing authority's published format and check-digit algorithm (HMRC weighted mod 97 (including the 2010 “+55” series)).

Can I check VAT numbers from code or in bulk?

Yes. The same check is available over the REST API (GET /v1/gb/vat/{id}) and the MCP server, with the same key as every other country. See the API docs.

Is this service affiliated with the United Kingdom tax authority?

No. HALPII Tax ID is an independent service run by HALPII S.A.C. (Lima, Peru). Results are informational, not legal or tax advice.

Other countries in Europe

All countries and verification levels

Last updated 2026-11-14. An independent service run by HALPII S.A.C. (Lima, Peru), not affiliated with or endorsed by any United Kingdom authority.