The Validate Tax Number endpoint in SIGN ES allows users to verify a NIF against the AEAT database or a VAT number against the VIES service.
We recommend using this endpoint to:
- Confirm that the recipient of an invoice is correct, helping prevent errors when the invoice is issued and transmitted to the tax authority.
- Validate data before creating a Taxpayer, ensuring the issuer’s details are correct prior to creating related resources.
NIF Validation (AEAT Service)
- The NIF validation endpoint only works in Production (LIVE), because the AEAT service does not provide a test environment.
- When calling this endpoint in TEST, the response will always be:
INVALID - For integration testing, you can use predefined tax numbers in TEST. Each number simulates a different outcome:
T00000001 → INVALID_SIMILAR
T00000002 → VALID
T00000003 → VALID_REMOVED
T00000004 → VALID_REVOKED
VAT Number Validation (VIES Service)
- The VAT number validation endpoint (for any EU country other than Spain) works in both TEST and Production (LIVE) environments.