VAT number batch validation: check multiple EU VAT IDs
VAT number batch validation checks multiple EU VAT IDs and keeps a separate VIES result for each one. Start with a CSV column named vat_number containing full VAT IDs, including country prefixes. This guide explains how to prepare that file, check it with your existing shared API key, and separate answered rows from unresolved checks.
CSV format for VAT number batch validation
Name the VAT column before importing a customer or supplier spreadsheet. Use vat_number, vat_id, vat or number as the column header; without a recognised header, the checker reads the first column.
Keep the country prefix and number together in each cell. If your spreadsheet has separate country and VAT-number columns, combine them before exporting the CSV. Keep the full VAT ID as text so leading zeroes are preserved; use EL for Greece and XI for Northern Ireland.
If the first column contains company names, label the VAT-number column with one of the accepted headers so the checker selects the IDs. Alternatively, paste one full VAT ID per line. Review duplicate and malformed rows before starting live checks: local formatting does not confirm VAT registration.
How to run VAT number batch validation from a CSV
1. Prepare the full VAT IDs, including each issuing country's prefix. Open the bulk checker to upload a CSV or paste the list, then review local format errors and duplicates before running the checks.
2. Verify your existing shared EORI + VAT API key and its remaining allowance. The bulk checker processes the list one number at a time; live lookups use that key and its monthly quota.
3. Download the dated results and review every row. A completed batch can still contain unresolved checks: completion does not mean that every VAT number is valid.
Read the result for each VAT number
Valid: VIES confirmed the VAT number for intra-EU transactions at the recorded check time. Review the returned company details where available.
Invalid: VIES did not confirm the registration. Ask the business to verify the number and its registration for intra-EU transactions; an unfinished registration or a recent change can also explain an invalid response.
Unavailable, timeout or rate limited: the check is unresolved. Keep these rows separate from invalid results. A local format error or duplicate row is also different from a completed VIES check.
Retry unresolved rows without repeating the whole batch
Save the completed results first, then use the retry CSV for unresolved numbers. Review your remaining usage before another run: a missing response does not prove that the server did not process the request.
The checker does not automatically retry failed requests. Check VIES service status and retry later if a registry is unavailable; no fixed recovery time is guaranteed.
Keep dated batch validation evidence
Keep the VAT ID, status, check time and source with the relevant customer or supplier record. The European Commission recommends keeping track of VAT validations in case of a tax control.
The bulk checker exports dated rows with local SHA-256 checksums. A checksum helps check file integrity; it does not turn a result into an official certificate or guarantee tax treatment.
What is VAT number batch validation?
It is a workflow for checking multiple VAT IDs through VIES from one CSV or pasted list. Each row keeps its own status, check time and unresolved state, so a failed request is not confused with an invalid VAT number.
Does a correct VAT format mean the number is valid?
No. A format check only checks the structure of the VAT ID. VIES retrieves registration information from national VAT databases; that response is needed to confirm the number for intra-EU transactions.
Do I need a separate API key for each country?
No. VAT Validate's bulk checker uses the existing shared EORI + VAT API key for the list. Include the correct country prefix with each VAT ID so each lookup reaches the appropriate registry.
Privacy and audit records
Teams may need validation evidence, but storage should be explicit and scoped to the user's compliance need.
A lightweight checker can avoid retention; a paid batch product should offer retention settings and downloadable evidence.
Validating VAT numbers at volume?
Join the batch/API list for CSV validation, retries, audit exports, and developer access.
Related VIES guides
- VAT validation for invoicesWhen to validate VAT numbers before issuing cross-border EU invoices.
- Reverse charge VAT number checkUse VIES as part of a reverse-charge VAT number check workflow.
- Keep VIES validation recordsWhy finance teams keep evidence of EU VAT number validations.
- XI VAT number checkerCheck XI VAT numbers and understand Northern Ireland VAT validation in VIES.
- Greece EL VAT numberWhy Greek VAT numbers use EL in VIES and how to enter them correctly.
- VIES not workingTroubleshoot VIES not working, unavailable member states, and failed VAT checks.