A Global Administrator signs in to the Microsoft Teams admin center, opens the Teams data export card on the Dashboard, picks a date range such as Entire history, then selects Export, and downloads the ZIP of JSON files from Analytics and reports then Usage reports then Downloads. Access to that tool is granted on request, supports tenants of up to 500 users, runs for 90 days, and the download link lasts 24 hours. Larger tenants export Teams content through Microsoft Purview eDiscovery instead, which needs a Microsoft 365 E3 or E5 license on the eDiscovery user and deletes search export packages 14 days after creation.
What it holds
Chats, group and meeting chats, channel messages, team and channel structure, membership, meeting records.
Find the size
The Microsoft 365 admin center shows message counts, not a byte figure: Reports then Usage then Microsoft Teams then Team usage lists Posts, Replies and Channel messages per team, and Export writes them to a CSV. Quote those message counts plus the team and channel counts.
What to enter on the form
Microsoft Teams in messages, and the year your company started using it. Seller form