From Guild Wars 2 Wiki
Squads are led by a commander. A squad is started by the commander creating a squad in the party menu. Players can then join the squad. There is no way for a commander to invite players to a squad at this time.
- You do not need the commander's permission to join a squad, but the squad is automatically disbanded if the Commander turns off the tag, changes characters, or leaves the game.
- Squads are limited to 50 players.
- Squad members can send messages via the squad chat channel, or .
- To leave a squad, type the chat command: /squadleave or go to the party window (click or "p") and press "leave" under squad.