Getting Started

Calling the API

Calls to the Transact API can be made in any programming language. The specific API calls you want to make will depend on your use case and business requirements.

Each API endpoint has its own scope and Resource Owner type (role) requirements, documented for each endpoint under Authorisation Requirements. If your request does not satisfy scope or role requirements, the API will return a 401 Unauthorized HTTP status code. For more information, see Scopes and Roles.

Make a call

All calls to the Transact API must include:

a Transact-Api-Version header specifying the API version to use
an Authorization header providing a valid access token using the HTTP Bearer scheme.

For example, using cURL to call GET /advisers might look like the following:

Code
curl \
  -H "Authorization: Bearer <token>" \
  -H "Transact-Api-Version: 2026-05-12" \
  https://apidemo.transact-online.co.uk/advisers

Future-proofing API calls

Breaking changes to the Transact API will only be introduced as part of a new major API version, which you must explicitly migrate to by changing the Transact-Api-Version header. This means that you should be able to build your integration to the current API version, and continue to use that code more or less unchanged until it is time to upgrade to a new version.

Non-breaking changes to the Transact API, such as adding a new endpoint or property, may be made without notice. To prevent compatibility problems, your application should implement the following behaviour when processing API responses:

Ignore unrecognised properties (instead of throwing an error), as adding new properties to a response object is not a breaking change.
Support unexpected values for string properties (such as wrapper type), as adding new possible values for a string property is not a breaking change.
- Note that this does not apply to properties with enum or pattern constraints (such as investor category).
Make no assumptions about API validation strictness, as relaxing validation constraints is not a breaking change.

For more information about changes to the Transact API, see the Changelog.

What's next

Authorisation Migrate from TRDS

Make a call

All calls to the Transact API must include:

a Transact-Api-Version header specifying the API version to use

an Authorization header providing a valid access token using the HTTP Bearer scheme.

For example, using cURL to call GET /advisers might look like the following:

Code

curl \
  -H "Authorization: Bearer <token>" \
  -H "Transact-Api-Version: 2026-05-12" \
  https://apidemo.transact-online.co.uk/advisers

Future-proofing API calls

Ignore unrecognised properties (instead of throwing an error), as adding new properties to a response object is not a breaking change.

Support unexpected values for string properties (such as wrapper type), as adding new possible values for a string property is not a breaking change.

Note that this does not apply to properties with enum or pattern constraints (such as investor category).

Make no assumptions about API validation strictness, as relaxing validation constraints is not a breaking change.

For more information about changes to the Transact API, see the Changelog.