- Currently an Office 365 tenant can have up to 500,000 teams.
- A global admin can create an unlimited number of teams. But a standard user can only create 250 teams.
- A team owner can add 2.500 members to a team.
- The current limit of members in a meeting is 80.
- There can be 20 members in a private chat, including the creator of the chat.
See here for more information https://docs.microsoft.com/en-us/microsoftteams/enable-features-office-365