EU VAT number validation
EU VAT number validation helps businesses confirm whether a customer VAT ID is active for cross-border EU transactions.
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?
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Related VIES guides
- VIES consultation numberLearn what a VIES consultation number is and when it can appear.
- VIES errors explainedMS_UNAVAILABLE, MS_MAX_CONCURRENT_REQ, TIMEOUT, INVALID_INPUT and SERVICE_UNAVAILABLE — what each VIES error actually means, whether to retry, and which member states are down right now.
- VIES service unavailableWhat to do when VIES or a national VAT registry is unavailable.
- Is VIES down?Live VIES status, country by country. See which EU member-state VAT registries are answering right now, read from the European Commission's own availability table every 15 minutes.
- MS_UNAVAILABLE VIES errorMS_UNAVAILABLE means a member-state VAT registry did not answer — it does not mean the VAT number is invalid. See which EU registries are down right now and when to retry.
- Invalid VAT number in VIESWhy an EU VAT number may appear invalid in VIES.