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How to check an EU VAT number
Updated: 1 November 2026 · Klik&Shop
Selling to a business in another EU country? You want to be sure your customer's VAT number is valid. Here is how to check it, manually or automatically.
Why check a VAT number?
For business-to-business (B2B) sales within the EU you can often charge 0% VAT or apply the reverse charge. One condition is that your customer holds a valid VAT identification number in another EU member state. If the number is invalid, the tax authority may claim the VAT from you. Checking before you invoice is wise. Read more in EU B2B reverse charge.
Step 1: check the format
An EU VAT number always starts with a two-letter country code followed by the national number, for example NL123456789B01 for the Netherlands. Every country has its own structure, and Greece uses EL instead of GR. See the format per country. A correctly formatted number is not necessarily valid.
Step 2: check it in VIES
VIES (VAT Information Exchange System) is the European Commission's system that asks the member state's tax authority in real time whether a VAT number is active for intra-EU trade. Learn what VIES is. The answer is valid or invalid. Many countries also return the registered name and address, so you can see whether the number belongs to your customer. Germany, for example, returns no name or address.
You can check a number right away with our free VAT number check, which queries VIES live.
Step 3: compare name and address
Does the name returned by VIES match the company on your order? A valid number belonging to someone else does not help you. If in doubt, ask your customer for confirmation.
Step 4: keep proof
Record when you checked the number and what the result was. For official proof, use the European Commission's VIES website and enter your own VAT number as well: you receive a consultation number showing that you performed the check at that moment.
What if VIES is down?
VIES or a national database is regularly unavailable for a while, often due to maintenance. An outage does not mean the number is invalid. Retry later and don't reject your customer straight away. See VIES down: what now?
Automate checks in your shop or invoicing
Checking many numbers, or building it into your checkout, CRM or bookkeeping? An API is easier than manual work. With the EU VAT Check API you validate numbers with one API call, with caching, batch checks of up to 50 numbers and clear errors during outages. See how to validate VAT numbers in your checkout.
FAQ
Is checking a VAT number free?
Yes. You can check an EU VAT number for free on the European Commission's VIES website or with the free check on this site (5 one-time free checks). For automated checks in software there is an API with 5 free checks per month and affordable prepaid credit.
What does invalid mean in VIES?
The number is currently not registered or not active for intra-EU trade in that country. First check for typos and the country code (e.g. EL for Greece). If it remains invalid, ask your customer for the correct number.
Can I check a UK VAT number in VIES?
No. Since 1 January 2021 UK (GB) numbers are no longer in VIES. Only Northern Ireland can still be checked for goods, using the XI prefix.
Check a VAT number now
5 one-time free checks via VIES, or automate with the API (5 free checks a month).