By default, you can have up to 200 members in a group. Only the group's owner can request to increase the group's limit.
If you want your group to be larger than 200 members, simply email support@GroupMe.com. In your request, be sure to include:
- the group name
- the new group limit
- the phone number you registered with GroupMe
It is possible to have remarkably large GroupMe groups, but keep in mind that groups larger than 200 people can get noisy. GroupMe is reply-all, so whenever a member replies to the group number, everyone in the group will get a text message or push notification. Additionally, everyone in the group has to respond to the group at least once in order to stay in.
Members are encouraged to text #stay to stay in the group, which doesn't send a message to the whole group.