Guides · Updated 6 October 2026

VIES is down: what it means and what to do

Why VIES fails for one country at a time, what its error messages mean, and how to keep invoicing correctly while it’s down.

Why VIES fails for one country at a time

VIES doesn't keep its own copy of every EU VAT number. When you check a number, it forwards the question to that country's tax database and passes the answer back. So when one national system is down, for maintenance, an overload or a fault, numbers from that country can't be checked while every other country carries on working. Some countries go down regularly at night or at weekends for planned maintenance.

Our live VIES status page shows which countries are answering right now, how long an outage has lasted, and recent history.

What the error messages mean

• MS_UNAVAILABLE: that member state's database isn't answering.
• MS_MAX_CONCURRENT_REQ / GLOBAL_MAX_CONCURRENT_REQ: too many checks at once, for that country or for VIES as a whole; try again in a moment.
• TIMEOUT: the national database took too long to answer.
• SERVICE_UNAVAILABLE: VIES itself is having problems.
• INVALID_INPUT: the number isn't in a format that country uses. This one is about the number, not an outage.

None of the outage errors mean the number is invalid. They mean nobody could say either way.

What to do while it's down

1. Don't treat the number as invalid, and don't start charging VAT to a customer you'd normally zero-rate just because of an outage.
2. Try again later. Most outages last minutes to a few hours.
3. Record that you tried: the time and the error. It shows you acted carefully if the transaction is ever questioned.
4. If you can't wait, ask the customer for their VAT registration certificate, or use the national tax authority's own lookup where one exists, then re-check in VIES once it's back.

How Validitool handles outages

• A check that VIES can't answer says "could not check", never "invalid".
• In bulk uploads, those rows are marked and can be checked again in one click, free.
• On the Scale plan, the API can return the last successful result for that number (up to 30 days old) during an outage, clearly marked as not live.
• Watched numbers are simply re-checked on the next daily run.

This guide is general information, not tax or legal advice. Rules and their application differ by country and by transaction; check with an adviser for your situation.

More guides

• How to check an EU VAT number before you invoice
• The reverse charge explained: EU and UK B2B sales
• How often should you re-check a customer’s VAT number?
• What proof of a VAT number check should you keep?
• EORI numbers explained: EU, GB and XI
• Northern Ireland XI numbers: VAT and EORI
• Checking Swiss and Norwegian VAT numbers
• Sanctions screening for small businesses
• Fake invoices and changed bank details: how to spot supplier fraud
• Peppol e-invoicing: what it is and how to check a customer