# VAT number verification via VIES

> Verify the validity of a VAT number from any EU member state through the European Commission VIES system, available over a REST API.

VIES is the European Commission system for verifying VAT numbers across the Union. For a cross-border supply of goods or services, a valid customer VAT number is a condition of the exemption.

## What the register contains
- Validity flag for the VAT number at the moment of verification
- Name and address of the entity as returned by that state's tax administration
- Timestamp of the verification

## Fields we return

| Field | Meaning |
| --- | --- |
| `vies_valid` | Whether the registration was valid at the time of verification. |
| `vies_verified_at` | When we performed the verification, in ISO 8601 format. |

## How to request the data

```http
GET /v1/company/ico/51636549?scope=tax

{
  "tax": {
    "ic_dph": "SK2120748862",
    "vies_valid": true,
    "vies_verified_at": "2026-08-23T00:14:12+02:00"
  }
}
```

## How often we update

On demand, with caching. VIES is a live European Commission service with its own limits, so we cache the result briefly and always return a timestamp so you know how old the verification is.

## What it is used for

When invoicing abroad, VAT number verification is a condition of the exemption. The stored timestamp has evidentiary value – it documents that you acted with due care at the time of supply.

In registration forms it validates the VAT number entered before you let the customer proceed.

## Frequently asked questions

### Why does VIES sometimes not respond?

VIES forwards the query to a specific state's tax administration, which may be temporarily unavailable. In that case we return an error, not the value false – not knowing and being invalid are two different things.

### How long does a verification result hold?

Legally what counts is the state at the time of supply, so for larger transactions we recommend verifying again. The vies_verified_at field tells you exactly when the check ran.