If you're an admin of an Atlassian Organization, we offer allowlisting a domain in the Admin Hub and SSO with Atlassian Access.
How it works:
Your Atlassian Org Admin will claim your domain within the Atlassian Org Admin Hub.
A new hire signs up to Trello on our main signup page using firstname.lastname@example.org as their email address
When they click the button to complete sign up, the user will become a managed member of your Atlassian Organization. If Atlassian Access is set up, Trello will also redirect them to the IdP associated with your company.
Once they've logged in, they'll be redirected into their Trello account.