EU VAT guide
EU VAT number validation
EU VAT number validation helps businesses confirm whether a customer VAT ID is active for cross-border EU transactions.
When to validate
Validate VAT numbers before relying on a cross-border B2B VAT treatment, and keep a record of the check for your files.
If the check fails, ask the customer to confirm the number and whether it is activated for intra-EU transactions.
Format comes first
Every EU country has its own VAT number format. A local format check catches obvious typos before VIES is queried.
Format validation is not the same as VIES validation; a correctly formatted number can still be invalid or inactive.
Validating VAT numbers at volume?
Join the batch/API list for CSV validation, retries, audit exports, and developer access.
Related VIES guides
- VIES VAT checkerCheck an EU VAT number in VIES and understand what the response means.
- VIES consultation numberLearn what a VIES consultation number is and when it can appear.
- VIES errors explainedUnderstand common VIES errors such as MS_UNAVAILABLE, TIMEOUT, and SERVICE_UNAVAILABLE.
- VIES service unavailableWhat to do when VIES or a national VAT registry is unavailable.
- Is VIES down?Check whether the VIES gateway appears reachable and learn what VIES downtime means.
- MS_UNAVAILABLE VIES errorUnderstand the MS_UNAVAILABLE VIES error and how to handle it.