MS_UNAVAILABLE
Member state VAT service is unavailable
What does MS_UNAVAILABLE mean?
The MS_UNAVAILABLE error means the VAT validation service for a specific EU member state is currently offline.
Each EU country maintains its own VAT validation service, and VIES acts as a gateway to these national systems. When a country's system is down for maintenance or experiencing technical issues, you'll get this error.
When does this error occur?
- During scheduled maintenance windows (often nights and weekends)
- When a country's national VAT system has technical problems
- During infrastructure upgrades or migrations
- Some countries have regular, predictable downtime; others are sporadic
Common maintenance patterns
Some member states have known maintenance windows:
| Country | Typical Maintenance |
|---|---|
| Germany (DE) | Frequent unplanned outages |
| Italy (IT) | Weekend maintenance common |
| France (FR) | Generally reliable |
| Spain (ES) | Occasional evening maintenance |
Note: These patterns change and aren't officially published by the EU.
Outages can last hours
Unlike rate limit errors that clear in seconds, MS_UNAVAILABLE often indicates extended downtime. A country's system might be offline for hours during maintenance or technical issues.
How to handle MS_UNAVAILABLE
1. Use a service with multiple data sources
VatDB queries multiple official EU and national databases. When a member state is unavailable through VIES, we can often validate through their national system directly. Set up webhooks to get notified when validation succeeds after a source becomes available again.
2. Don't retry aggressively
Unlike rate limits, service outages don't clear quickly. Aggressive retries waste resources. Wait at least 5 to 10 minutes before retrying.
3. Implement a circuit breaker
After several failures for a country, stop trying and fail fast. Use cached results or queue for later processing.
Validate even when countries are offline
VatDB maintains connections to multiple official EU and national databases. When a member state is unavailable through VIES, we query alternative sources directly. Get validation results even during VIES outages, and use webhooks to handle async validation when services recover.
Try VatDB FreeFrequently Asked Questions
How long do MS_UNAVAILABLE errors typically last?
It varies. Scheduled maintenance might last a few hours overnight. Unplanned outages can last from minutes to a full day. Germany's systems are particularly prone to extended availability issues.
Is there a way to check which countries are available?
VIES doesn't provide a status API. You can only discover unavailability by attempting a validation. VatDB monitors availability continuously and can route around outages automatically.
Should I retry MS_UNAVAILABLE errors?
Not immediately. Unlike rate limits, service unavailability typically indicates a longer outage. Wait at least 5 to 10 minutes before retrying, or use a service with alternative data sources.
How does VatDB handle MS_UNAVAILABLE?
VatDB connects to multiple official data sources directly, bypassing VIES when needed. When a country's VIES connection is down, we validate through alternative national databases. You can also use webhooks to get notified when validation completes.
Can I validate VAT numbers from other countries while one is down?
Yes. MS_UNAVAILABLE affects only the specific country. You can still validate VAT numbers from other EU member states that are online.