API Integration

vatcheck.tax provides a high-performance REST API designed to help B2B platforms automatically verify UK and European VAT registration numbers directly within their checkout or invoicing flows.

Endpoint: Verify Bulk VAT Numbers

Request Headers

• Authorization: Bearer YOUR_API_KEY
• Content-Type: application/json

Request Body (JSON)

Submit an array of up to 100 VAT strings. The API Gateway utilizes Smart Routing to automatically determine whether to query the HMRC or VIES databases.

{
  "vatNumbers": [
    "GB123456789",
    "DE987654321"
  ]
}

Example Response

The API returns a consolidated array of result objects. Note the presence of the reverseChargeEligible flag, which helps automate your tax rules for EU/UK cross-border trade.

{
  "results": [
    {
      "vatNumber": "GB123456789",
      "countryCode": "GB",
      "valid": true,
      "businessName": "UK Example Limited",
      "address": "123 London St, UK",
      "timestamp": "2026-04-01T10:00:00.000Z",
      "routing": "HMRC API",
      "reverseChargeEligible": true
    },
    {
      "vatNumber": "DE987654321",
      "countryCode": "DE",
      "valid": true,
      "businessName": "DE Enterprise GmbH",
      "timestamp": "2026-04-01T10:00:00.500Z",
      "routing": "European Commission VIES API",
      "reverseChargeEligible": true
    }
  ]
}

Rate Limiting & Errors

Standard SaaS Plans are limited to 100 requests per minute. Exceeding this limit will return an HTTP 429 Too Many Requests error. If an upstream government registry is offline, the endpoint may return HTTP 503 Service Unavailable.