Rules of the game in badminton

At the start of a game, the toss decides which player may start or choose the half of the game. In the second game and in any third game, the side that won the previous game serves first.

All games are played to 21 points. A side that has won two games is the winner. The party that wins a rally scores a point, regardless of whether it has service or not. The party that wins the rally must also serve at the next rally.

If the score becomes 20-20, the game must be won with 2 points difference. If the score becomes 29-29, the side that scores the 30th point wins the game.

The service is performed according to its own score at 0, 2, 4, 6, ... into the right service box and at an odd score into the left service box. The service must always be hit to the diagonally opposite serving box.

In doubles, the players of the serving side decide before the start of a game who will serve first. The server does not change service box until his side has scored a point during his service game.

The serving side remains on service until his side loses a rally. When the service is regained, the partner shall start serving from the other box.

The service is always received in the diagonally opposite service box. 

In doubles, the players of the receiving side decide before the start of a game who receives the first service.

Players of the receiving side do not change service box while the other side has service. The player of the receiving side who served last stands in the box according to their score. His partner receives the services in the other box. As soon as the service is regained, the partner serves first from the box he was standing in.

The order of serving is fixed throughout the game:

• from the initial server who started the game from the right-hand serving box;
• to the partner of the initial server. He serves from the left-hand serving box;
• to the partner of the initial server;
• to the initial receiver;
• to the initial server;
• and so on

Note: At service-over, there is no box change. This happens only after a point is scored on own service. If both sides score only 1 point each time, no one will switch squares during that game.

• A part of the shuttle is above the server's waist on service;
• Both feet of the server or receiver are not within the serving box;
• The handle of the server's racket does not point down at service;
• In an attempt to serve, the server hits next to the shuttle;
• The shuttle falls to the floor after service without being touched by the opponent outside the service box;
• The shuttle lands outside the court or is hit next to, under or through the net;
• A player touches the shuttle, net or post with his body or clothing during play;
• The shuttle hits the ceiling or another object;
• A player deliberately attempts to mislead or obstruct the opponent or delays play in an unauthorised manner.

If the opponent was not ready at service.

• When discussing in or out;
• In case of interference from outside;
• If during the rally the shuttle gets stuck on the net or, after having passed over the net, gets stuck in the net.
• If during the rally the cap of the shuttle becomes completely detached from the calyx;
• In the event of an unforeseen event.

It is not a foul if the shuttle hits the net during a rally or at service and then still falls into the field of play. Boundary lines always belong to the field in question.