Linking a Trello Enterprise to an Atlassian organization

You can link your Trello Enterprise to an Atlassian organization to use the free domain claim feature available to Atlassian Organizations, and take advantage of Enterprise features for managed accounts. You can set up an Atlassian organization and claim a domain for free at admin.atlassian.com. 

To link your Enterprise and your Atlassian organization together, go to the Atlassian settings tab in your Trello Enterprise admin dashboard. On that page, you’ll see a list of any organizations that can be linked to your Enterprise. Click the “Link organization” button to link the two together. Once you confirm this action, your Enterprise and organization will be linked, and the name of your Enterprise will be replaced by the name of the organization.

If you’re not the admin for your Atlassian organization, you’ll need to either add the organization admin as an admin for your Enterprise or ask them to make you an admin for the organization. An Enterprise can only be linked to an Atlassian organization by someone who is an admin for both.

Managed members 

When an Enterprise and an Atlassian organization are linked, they’ll share the same set of managed members, based on the organization’s claimed domains. Any Trello user with an email address on the claimed domain will be a managed member of both the Enterprise and the organization. Managed members will not count toward your Enterprise license seats unless they are given an Enterprise license or added to an Enterprise Workspace.

Only users on the claimed domain can be managed by the Enterprise. If your Enterprise was previously managing users from different domains, they will no longer be managed—however, those users can still be granted an Enterprise license and will still be able to access any boards or Workspaces within your Enterprise that they were already a member of.

Provisioning users via SCIM 

Trello's SCIM API is in the process of being retired. The best way to provision access to Trello is to provision an Atlassian Account for a user using the Atlassian SCIM API or integration with your identity provider, then invite them to the appropriate Trello Workspace from the Workspace's members tab, or through the Trello REST API.
For most organizations, users provisioned to an Atlassian Org will not be granted a Trello Enterprise license automatically. A license can be granted by inviting that user to an Enterprise workspace. 
Invited users are not immediately billable in Atlassian Guard Standard. They become billable in Atlassian Guard Standard when they log into Trello for the first time.