When is a shuttle a fault?

Under Law 13 of the BWF Laws of Badminton, it's a fault if, in play, the shuttle:

• lands outside the court (a shuttle on the line is in: lines are part of the area they mark);
• fails to pass over the net, or goes through or under it;
• touches the ceiling or side walls;
• touches a player's body or clothing;
• touches any other object or person outside the court (a venue can make local bye-laws for obstructions such as low beams);
• is caught and held on the racket and then slung during a stroke;
• is hit twice in succession by the same player (hitting the frame and strings in one stroke is fine);
• is hit by a player and then their partner in succession; or
• touches a player's racket and doesn't travel towards the opponent's court.

On the serve, it's also a fault if the shuttle is caught on top of the net, is caught in the net after passing over it, or is hit by the receiver's partner.

A shuttle that hits the net or post and starts falling on the striker's side is no longer in play.