# VIES service unavailable

> The EU VAT validation service goes down regularly and has no uptime guarantee. What that means for your check, and what to do next.

Canonical: https://vetthisvendor.com/guide/vies-service-unavailable
Published: 2026-08-02. Updated: 2026-08-02.
Author: Jose Pollman, VetThisVendor.

If a check came back as **"Could not check"** for the VAT number, the registry did not
answer. That is not a statement about the supplier — it is a statement about the service.

## Why this happens so often

VIES is not one system. It is a thin front end that forwards each query to the tax
authority of the country in question, and it publishes no uptime guarantee for either
part. When Italy's registry is down, Italian VAT numbers cannot be checked, even though
VIES itself is fine.

This is normal, not exceptional. Some national registries have scheduled nightly
maintenance windows, and several are noticeably less reliable outside business hours in
their own time zone.

## The dangerous part

VIES answers an unreachable member state with a *negative* result rather than an error —
the response says "not valid" and puts the actual reason in a separate field. Tools that
read only the first field will tell you a perfectly legitimate supplier's VAT number is
invalid.

This tool reads the reason field and reports "could not check" instead. If another
service tells you a number is invalid and this one says the registry was unavailable,
that discrepancy is why.

## What to do

1. **Try again in a few minutes.** Most outages are short.
2. **Try again during the country's business hours** if it keeps failing — national
   registries are more reliable then.
3. **Do not treat it as a red flag.** An unavailable registry says nothing about the
   supplier.
4. **Check the other three results in the meantime.** The IBAN checksum, sanctions
   screening and sending-domain checks do not depend on VIES and will have completed
   normally.

## If you need a definitive answer today

For an EU number, the tax authority in the supplier's own country can confirm
registration directly. For a UK number, HMRC publishes its own checker. Both are slower
than VIES but do not depend on it.

Whatever the registry says, confirm bank details by phone using a number you already had
— not one from the invoice or email. Registry status and payment safety are different
questions, and the second one is the one that costs money.