UK VAT Number Verification

Post-Brexit note: Since 1 January 2021, UK VAT numbers are no longer available through the EU VIES system. UK VAT must be verified separately via HMRC's own API or VAT registration checker.

UK VAT format check & verification

UK VAT number (with or without GB prefix)

Standard UK VAT: GB + 9 digits. Branch traders: GB + 9 digits + 3 digits. Government entities: GBGD/HA + 3 digits.

Official service: api.service.hmrc.gov.uk/organisations/vat/check-vat-number

Enter a UK VAT number above to check the format.

UK VAT number formats

Type	Format	Example	Notes
Standard	`GB + 9 digits`	`GB123456789`	Most common — applies to sole traders, partnerships, companies
Branch trader	`GB + 9 digits + 3 digits`	`GB123456789001`	For businesses with multiple VAT registrations (branches)
Government (central)	`GBGD + 3 digits`	`GBGD001`	Central government departments
Government (health)	`GBHA + 3 digits`	`GBHA500`	Health authorities

Brexit and UK VAT: key changes

When the UK left the EU on 31 December 2020, UK VAT numbers were removed from the European Commission's VIES database. Businesses trading with UK entities can no longer use VIES to verify UK VAT numbers.

UK VAT verification must now be done via HMRC's dedicated VAT verification API or online checker.
Northern Ireland has a special status: NI businesses trading in goods with the EU retain an XI VAT number prefix for VIES purposes under the Windsor Framework.
For EU–UK cross-border trade, both EU and UK VAT registrations may be needed depending on the goods, supply chain, and fiscal representative requirements.
Import VAT applies to most goods entering the UK from the EU, and vice versa, following the end of the transition period.

Northern Ireland: XI prefix

Under the Windsor Framework (formerly the Northern Ireland Protocol), businesses established in Northern Ireland that trade in goods with EU member states use an XI prefix for VAT purposes on those transactions.

This means Northern Ireland businesses may have both a GB-prefixed UK VAT number (for UK domestic purposes) and an XI-prefixed number that is valid on VIES for goods trading with the EU. Services transactions from Northern Ireland use the standard GB number.

Common UK VAT format mistakes

Mistake	Example	Correction
Missing GB prefix	`123456789`	`GB123456789`
Lowercase prefix	`gb123456789`	`GB123456789`
Spaces from invoice copy	`GB 123 4567 89`	`GB123456789`
Wrong digit count	`GB12345678` (8 digits)	Standard format requires 9 digits after GB
Using VIES to check UK number	Searching `GB123456789` on VIES	Use HMRC checker — GB numbers are not on VIES post-Brexit
Confusing XI with GB	Using `GB` prefix for NI goods trades to EU	Northern Ireland goods trades to EU use `XI` prefix on VIES

UK VAT for EU businesses: practical considerations

EU businesses that sell goods or services to UK customers may need to register for UK VAT depending on the nature and volume of their supplies. Since Brexit, several new rules apply that did not exist under the single market framework.

Goods sold to UK consumers (B2C): Overseas sellers who sell goods to UK consumers must register for UK VAT if their supplies exceed the £90,000 threshold, or if they use an online marketplace which may collect VAT on their behalf.
Low-value imports (under £135): VAT is collected at the point of sale for goods under £135 sold to UK consumers by overseas sellers — rather than at the border. This requires the overseas seller (or marketplace) to be UK VAT registered.
B2B sales to UK businesses: Typically subject to the UK reverse charge mechanism. The UK customer accounts for VAT, so no UK VAT registration is needed by the EU supplier in most cases.
Services: Most B2B services supplied to UK businesses by EU providers are outside scope for UK VAT (the place of supply is the UK, but the recipient accounts for it via reverse charge). B2C digital services may require UK VAT registration.

UK VAT rules for overseas sellers and digital services are complex. The guidance above is general in nature. Always consult a UK tax adviser for your specific business situation and supply chain structure.

Recording UK VAT verification evidence

As with EU VAT checks, HMRC guidance recommends that businesses keep a record of UK VAT verification checks as part of their supplier onboarding and invoicing processes. This is especially relevant for businesses applying the reverse charge mechanism, claiming input VAT, or preparing for an HMRC compliance check.

A basic verification record should include:

The UK VAT number checked (including GB prefix)
The date and time the check was carried out
The result returned by the HMRC VAT checker (valid/invalid, business name if shown)
The name of the person who carried out the check

HMRC provides a VAT number validation API that businesses and accountancy software can integrate for automated checks. The HMRC "Check a UK VAT number" service at gov.uk/check-uk-vat-number is the manual equivalent for individual checks.

After the verification

Post-Brexit, UK VAT runs on its own track

Verification is the easy part. UK VAT registration thresholds, Making Tax Digital filing, and the import VAT mechanics that come with selling into Britain from the EU — that's where teams spend real time. Two services worth knowing about:

Hellotax

Ecommerce / FBA

UK VAT registration, MTD-compliant filing, and Amazon UK marketplace handling alongside EU obligations. Built for sellers managing both sides of the Channel under one roof rather than two separate setups.

Learn more about Hellotax

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