Bring teammates to your Teams free org. Now in Teams free you can choose to invite directly from your Microsoft account or send an invite link.
Invite via your Microsoft account
Select Chat or Teams on the left side of the app, then select Invite others to your org.
Select Invite your contacts to choose from your list of email contacts, or select Invite by email to manually enter who you want to get an invite. (If you choose by email, type the emails and names of people you’d like to add to your org. (Select Add more if you have more people you'd like to add.)
Note: By default, both admins and members can add new members to Teams free. Admins can also restrict the ability of members to add new members.
Select Send invites to send each person an email invitation to join the org.
Note: If an invitation doesn't go through, try resending it. Even if that person gets multiple invites, they can only join once.
Once they've joined your Teams free org, add them to a specific team you've created.
You're currently able to add up to 300 people to your Teams free org.