Agent Authorisation API
| REST | |
| Version 2.0 - beta | |
| 17 February 2026 | |
| Sandbox base URL | https://test-api.service.hmrc.gov.uk |
| Production base URL | https://api.service.hmrc.gov.uk |
Overview
Use the Agent Authorisation API to:
- request authorisation to act on a client's behalf for either Making Tax Digital for VAT or Making Tax Digital for Income Tax
- cancel an authorisation request
- check the status of authorisations already requested
- query active or inactive relationships
For information on how to connect to this API see the Income Tax MTD end-to-end service guide.
Errors
Errors returned by this API are listed in the Response section of each endpoint. Read the reference guide for more information about errors.
Testing
You can use the Sandbox environment to test this API. You can test different scenarios in the Sandbox by passing the Gov-Test-Scenario header. The Sandbox also allows you to perform stateful and dynamic testing for some APIs. The ‘Test data’ section under each endpoint explains the test scenarios that can be simulated.
If you have a specific testing need that is not supported in the Sandbox, contact our Software Developers Support Team. Some endpoints may be marked ‘[test only]’, which means that they are not available for use in Production and may change.
Fraud Prevention
Fraud prevention headers are not required for this API
Versioning
When backwards-incompatible changes are made to this API, we release a new version. Read the reference guide for more information about API versioning. For updates about all our APIs, refer to the API changelog.
Endpoints
| Version | Environments | Endpoints |
|---|---|---|
|
Version 2.0 - beta
(opens in new tab) |
Sandbox and Production | 2.0 endpoints |
|
Version 1.0 - beta
(opens in new tab) |
Sandbox and Production | 1.0 endpoints |