A valid EU VAT number is the gatekeeper for zero-rated cross-border B2B invoices, so getting it wrong means a tax exposure. This validator takes any VAT number, auto-detects the issuing member state from its 2-letter prefix, and applies that country’s specific rule — making it a single tool for all 27 EU formats instead of 27 separate checkers.
How it works
Every EU VAT number begins with a 2-letter country code (with one quirk: Greece uses EL, not GR). The tool:
- Strips spaces, dots and dashes and uppercases the input.
- Splits off the 2-letter prefix and matches it to a member state.
- Tests the remaining body against that state’s structural pattern — length and the right mix of digits and letters.
- Where the member state publishes a deterministic check digit, runs that algorithm too.
Seven member states have public, verifiable check digits, all implemented here:
- DE — ISO 7064 MOD 11,10 over 8 digits
- NL — the “elfproef” mod-11 weighting on the 9-digit core
- IT — Luhn checksum over 11 digits
- AT — weighted mod-10 with digit-folding
- FI — weighted mod-11
- LU — first 6 digits modulo 89 equals the last 2
- IE — weighted mod-23 mapped to a check letter
The other states are format-checked only, because they do not expose a public check-digit rule.
Example and notes
Enter DE136695976. The tool detects Germany, confirms the 9-digit format, runs MOD 11,10 over 13669597, and matches the final 6. Try changing a digit and the check digit fails with the expected value shown.
A pass here means the number is internally consistent — it does not confirm the business is VAT-registered or active. For that, query the official EU VIES service. All processing stays on your device, so you can validate supplier lists safely.