Tech Tips: Signal lets users create groups with up to 1000 members, here is how to create one Tech Tips: Signal lets users create groups with up to 1000 members, here is how to create one A New Group is only available for Signal contacts who have updated Signal on all their devices. Signal Desktop does not support the creation of new groups. However, Signal Desktop supports receiving messages from new and legacy groups. advertisement (Picture: Reuters) Signal lets users add up to 1000 messengers in a group that shares encrypted messages. A New Group is only available for Signal contacts who have updated Signal on all their devices.