What VIES checks
According to the European Commission, VIES is a search engine, not a database: each query is answered from the national VAT database of the country concerned. A 'valid' answer means the number is registered there for intra-EU trade. An 'invalid' answer means it is not registered in that database, because the number does not exist, has not been activated for intra-EU transactions, or its registration is not yet finalised; changes may not show up immediately. (source, verified 2026-10-11)
“Not valid” is different from “no answer”
A VIES check can end in three ways:
- Valid — VIES confirmed the number at the time of the check.
- Not valid — VIES answered and did not confirm the number.
- No answer — VIES or the member state’s database did not respond (official codes such as
SERVICE_UNAVAILABLE,MS_UNAVAILABLE,TIMEOUT,GLOBAL_MAX_CONCURRENT_REQ,GLOBAL_MAX_CONCURRENT_REQ_TIME,MS_MAX_CONCURRENT_REQ,MS_MAX_CONCURRENT_REQ_TIME). This tells you nothing about the number. Try again later.
A format check, like ours, is not a VIES answer: it only tests whether the number has the structure expected for that country, not whether it is valid. See the formats guide.
Practical steps when a number is “not valid”
- Re-check the input: prefix, missing digits, letters confused with digits.
- Ask your customer to confirm the number and whether it is registered for intra-EU trade.
- Check again later — a newly issued number may take time to appear.
- Check it in the European Commission’s official VIES checker.
Whether you may still apply the reverse charge without a confirmed number depends on national rules; ask the tax authority or an adviser.
Sources
- https://europa.eu/youreurope/business/finance-and-tax/vat/check-vat-number-vies/index_en.htm (verified 2026-10-11)
Information only, not tax advice.