After the Bulk Validate Tax Numbers request, this request retrieves the status and results of a bulk tax number validation. Use it to monitor processing progress, check how many tax numbers have been validated, or retrieve previously submitted results by specifying the associated request identifier. Each response returns up to 100 validation results.

To return an update on how many tax numbers have been processed, use the following URL and the GET method:

GET https://{service_url}/bulk/api/v3/tax_numbers/validate

The {service_url} is the base URL of the service environment.

You can also use this request to retrieve previously created results by specifying the request_id in the URL. For example, send a GET request to the following endpoint.:

GET https://tax-id-validator-bulk-api.sandbox.marketplace.taxamo.com/bulk/api/v3/tax_numbers/validate

Considerations

The response returns up to 100 results per request.

Details

Endpoint	Method
`/bulk/api/v3/tax_numbers/validate`	GET

Response parameters

The following parameters are returned in the response:

Field	Description
`items.status`	Provides the overall validation status for the tax number processing result.
`items.status.request_id`	Identifies the original request that submitted the tax number validation.
`items.status.id`	Identifies the specific validation result. This identifier can be used with the Poll Last Seen Result request to retrieve incremental updates.
`items.status.output.buyer_tax_number_valid`	Indicates whether the tax number is valid.
`items.status.output.buyer_tax_number_format_valid`	Indicates whether the tax number format and syntax are valid.
`items.status.output.buyer_tax_number_Validation_info`	Provides additional details about the validation outcome, such as syntax or verification errors (for example, `tax-number-syntax-invalid`).
`items.status.output.buyer_tax_number_normalized`	Returns the tax number in a standardized, normalized format.
`items.status.output.buyer_tax_service_cache_used`	Indicates whether a cached validation result was used instead of real-time validation.
`items.status.output.buyer_tax_service_cache_timestamp`	Returns the timestamp when the cached validation result was stored.
`tax_number_service`	Identifies the external service used to validate the tax number (for example, VIES).

The response also contains the same output fields as any other Vertex Validator response.

Sample request

GET https://tax-id-validator-bulk-api.sandbox.marketplace.taxamo.com/bulk/api/v3/tax_numbers/validate

Sample response

{
    "items": [
        {
            "status": "processed",
            "request_id": "ANKpMhAXMAA=",
            "id": "CMGpMhACMAA=",
            "output": {
                "buyer_tax_number_valid": false,
                "buyer_tax_number_format_valid": false,
                "buyer_tax_number_validation_info": "tax-number-syntax-invalid"
            }
        },
        {
            "status": "processed",
            "request_id": "ANKpMhAYMAA=",
            "id": "CMGpMhAFMAA=", 
            "output": {
                "buyer_tax_number_valid": false,
                "buyer_tax_number_format_valid": true,
                "buyer_tax_number_validation_info": "tax-number-invalid-according-to-external-service",
                "buyer_tax_number_normalized": "111111111",
                "buyer_tax_number_service_cache_used": true,
                "buyer_tax_number_service_cache_timestamp": "2025-08-20T15:07:34Z",
                "tax_number_service": "tax.service.gov.uk.api"
            }
        }
    ]
}