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How VATcheckly works
1. Format check
We first clean up the input (spaces, dots and dashes are removed, and a Greek GR prefix becomes EL) and check it against the official format for that country. A number in the wrong format is rejected straight away with the expected format, without sending anything to VIES. See VAT number formats by country.
2. Live VIES request
A correctly formatted number is sent to the European Commission's VIES REST service, which asks the tax authority of that country in real time. The answer has three possible states:
- Valid: the number is registered for intra-EU transactions. Most countries also return the registered name and address.
- Invalid: the country's tax authority says the number is not active for intra-EU trade.
- Unavailable: the country's system didn't answer. We never report this as invalid.
3. Retries
When VIES reports a temporary overload or timeout, we retry up to three times with a short pause. If a whole country is down (MS_UNAVAILABLE) we stop and tell you, rather than hammering a system that's offline. In bulk jobs, numbers from unavailable countries are retried automatically, up to six times, as the country comes back. See VIES error codes.
4. Caching
Results of free checks are cached for 24 hours, so checking the same number twice in a day doesn't count against your limit or load VIES. Checks that include your own VAT number as the requester are always sent live, because each one produces its own consultation number.
5. Proof for your records
If you add your own VAT number as the requester, VIES returns a consultation number: a unique reference that shows who checked which number and when. Paid plans store it with a printable proof page. Read why the consultation number matters.
6. VIES status monitor
Every 5 minutes we read the availability that VIES itself reports for each member state and record it. The VIES status page shows the current state and 7-day uptime per country. Status history is kept for 90 days.
7. VAT rates
The VAT rates and calculator use rates maintained by hand from official sources, last reviewed on . Rates change, so for invoices always confirm the rate for your specific goods or services.
VATcheckly gives general information, not tax advice. Results come from VIES "as is"; keep your own records.