Check VAT tax number

A VAT tax number is the registration ID assigned to businesses registered for Value Added Tax — the same identifier often called a VAT number or VAT ID on invoices. Before you pay a supplier, issue a zero-rated B2B invoice, or onboard a trading partner, you should check a VAT tax number against the official registry. It takes seconds, costs nothing, and confirms the registration is real and currently active.

What is a VAT tax number?

In the UK and EU, a VAT tax number identifies a business registered to charge and reclaim VAT. UK numbers use the prefix GB followed by nine digits — for example GB116300129. EU numbers start with a two-letter country code: IE for Ireland, DE for Germany, FR for France, and so on. The terms VAT number, VAT ID, and VAT tax number refer to the same registration in most B2B contexts. Format rules for GB are in UK VAT numbers; EU prefixes are in EU VAT numbers explained.

How to check a VAT tax number online

To check a VAT tax number online, enter the full code including its country prefix into a tool that queries the official registry live. GB numbers are validated through HMRC; EU member states use the European Commission's VIES system. You receive an instant valid or invalid status plus the registered business name and address where the authority provides them.

Use our free VAT checker on Check VAT Number for both UK and EU lookups — no account required. For step-by-step guidance, read how to check VAT registration number and how VAT validation works.

UK vs EU VAT tax number checks

The country prefix tells you which registry to use. Since Brexit, GB numbers no longer go through VIES — they require an HMRC lookup. All 27 EU member states use VIES. If you trade across both markets, you need both workflows. See VIES vs HMRC: what's the difference? for a full comparison. UK-specific guides include check VAT number in UK and how to verify a UK VAT number online.

What a VAT tax number lookup returns

A successful VAT tax number lookup confirms whether the registration is active right now. When valid, you also get the company name and address the tax authority holds on file — compare those details to your supplier or customer before releasing funds. An invalid result means you should pause payment and investigate. Follow what to do if a VAT number is invalid and read why you should verify VAT numbers before every B2B transaction.

When to verify a VAT tax ID

Build a verify VAT tax number step into supplier onboarding, accounts payable, and high-value invoice approval. A VAT tax ID check before the first payment protects against invoice fraud — see how to spot VAT invoice fraud. For Irish suppliers, read how to check a VAT number in Ireland. Company-specific tips are in how to check a VAT number for a company and our FAQ.

Check a VAT tax number free now

Whether you need a one-off free VAT tax number check or a regular business VAT tax number verification workflow, the process takes seconds. Visit the Check VAT Number homepage, enter the full number with its country prefix, and get instant HMRC or VIES results — or browse more guides on our blog.