We recently communicated that on October 11, 3E Cloud is migrating to our new authentication regime. For APIs, the 3E Cloud migration to Elite ID requires any external applications that are currently using 3E REST or OData APIs to migrate to new endpoints where the new authentication regime is implemented. Customers and Partners are required to complete the following by November 30, 2023:

  • Customers must generate and provide credentials to new endpoints to third-parties and internal parties whose applications currently use the 3E APIs. Applications will have to be reconfigured with new credentials and reimplemented with the new APIs. Please refer to Section B: Setting Up Third Party Client Apps to Authenticate with Elite ID in the TR-21075: Migrating to Elite ID document for details about the migration process.
  • Partners and third party integrators must reimplement their applications to use the new endpoints for their Cloud Customers. Credentials will now be managed by each customer. Thus, you must request new credentials from the customer to reconfigure the application and reimplement to use the new endpoints. Please refer to "Calling 3E APIs with New Elite ID Authentication Method" within "Configuring Your Third-Party Application Integrations" for details about the migration process. These sections are found under Section B: Setting Up Third Party Client Apps to Authenticate with Elite ID in the TR-21075: Migrating to Elite ID document.


3E’s API provides access to data resources in the 3E financial management system. The API provides the ability to retrieve, add, or modify records (e.g., Clients and Matters) – and more.
This API expands 3E’s integration capabilities beyond the Elite Service Bus (ESB) file imports and exports integration method. The API allows third-party solutions and Thomson Reuter customer development teams to build real-time integrations with 3E. The API serves as a hub that provides a single secure integration point. The Hub routes both 3E hybrid and cloud only requests.


  • Provide flexible and robust capabilities and services that enable your firm to differentiate from the competition
  • Integrate 3E data with other applications (e.g., case management system) to streamline workflows, save time, and reduce errors and costs
  • Combine 3E data with other firm data and gain deeper insights for effective decision-making
  • Let your lawyers continue to use their favorite time entry app, while integrating that system with 3E. Eliminating any learning curve or down-time
  • Delve into the analytics by integrating your existing reporting suite with 3E’s real-time data
  • Add “Who Knows Who” relationship intelligence to your firm’s CRM system. Keep contacts and relationships up to date. Retrieve contact details and relationships by company and person
  • Retrieve and write time card data to/from 3E


3E APIs are available to customers running 3E on premises and 3E Cloud customers. The 3E REST APIs were officially released in July 2019 with our 3E 2.9.1 release but are available for customers on 3E 2.8.1 and above.

For customers operating on premises, the 3E REST API end point is automatically installed with your 3E User Interface packages thus should be able to access 3E APIs via endpoints shown in Swagger at [Your3EServerName]/[Your3EInstanceName]/Web/Swagger. Windows Authentication is used to authenticate to on premises 3E APIs.

For cloud customers, please contact Thomson Reuters support via https://customerportal.elite.com/ to request the credentials (client ID and secret) to access 3E APIs. Please refer to Knowledge Base article TR-19784: How to obtain access to 3E APIs for help with opening a case. Support will resolve your case by providing the API credentials. Customers engaged in an implementation project should work with the project team to obtain 3E API access.

Third party integrators, including 3E partners or new vendors interested in building API based integrations with 3E, we encourage you to work the 3E APIs directly on your 3E instance. Thomson Reuters does not yet offer a 3E integration sandbox. Alternatively, if you are working with a 3E customer, you may work with the customer to access their 3E, on premises or in the cloud. New to Thomson Reuters partnership program? Please contact Greg Brown.

When you have obtained access to 3E APIs, the below are great ways to get you started on your integration/APIs access journey:

  • Core Resources – View for a list of available 3E Resources (i.e., Attachment, Time, Matter, etc.) an integrated application can access.
  • API Authentication – Follow the steps here to get started using the 3E API.
  • Sample App – Download this sample application to learn how the 3E API works.
  • 3E API Reference – View for a comprehensive list of API resources, endpoints, methods, and schemes.
  • Knowledge Base – The Thomson Reuters Knowledge Base contains 3E API Release Notes as well as other reference material for the 3E APIs. See article TR-19780: 3E API References and Information for more information.
Last Updated: Oct 11,2023