This version is in beta - expect some breaking changes.
Business Source Adjustable Summary (MTD) API
|Available in Sandbox||Yes|
|Sandbox base URL||https://test-api.service.hmrc.gov.uk|
|Available in Production||Yes|
|Production base URL||https://api.service.hmrc.gov.uk|
The Self Assessment BSAS (Business Source Adjustable Summary) API allows a developer to retrieve an adjustable summary calculation for a specified self-employment or UK property business, for a given accounting period. Here a developer can:
- generate a list of business source adjustable summaries
- generate an end of accounting period BSAS
- request a specific BSAS
- request the adjustments made to a specific self-employment BSAS
- provide accounting adjustments against a specified BSAS
- request the adjustments made to a specific UK property BSAS
You can find the changelog in the self-assessment-bsas-api GitHub wiki.
It may not be possible to test all scenarios in the sandbox. You can test some scenarios by passing the Gov-Test-Scenario header. Documentation for each endpoint includes a Test data section, which explains the scenarios that you can simulate using the Gov-Test-Scenario header.
If you have a specific testing need that is not supported in the sandbox, contact our support team.
Some APIs may be marked [test only]. This means that they are not available for use in production and may change.
When an API changes in a way that is backwards-incompatible, we increase the version number of the API. See our reference guide for more on versioning.
We use standard HTTP status codes to show whether an API request succeeded or not. They are usually in the range:
- 200 to 299 if it succeeded, including code 202 if it was accepted by an API that needs to wait for further action
- 400 to 499 if it failed because of a client error by your application
- 500 to 599 if it failed because of an error on our server
Errors specific to each API are shown in the Endpoints section, under Response. See our reference guide for more on errors.