Decision path
Identify the source before deciding fault or let
- Was the shuttle in play when the disputed act occurred?
- Was the act by a player, a coach, or someone outside the match?
- Did a player invade under the net and obstruct or distract an opponent?
- Did a player prevent an opponent from making a legal stroke whose follow-through could cross the net?
- Was a player’s shout, gesture, or other action a deliberate distraction?
- Did a coach actually disrupt play or distract the opposing player in the umpire’s opinion?
- If advice was being given, had the next server and receiver already taken up position?
These questions matter because the consequences differ. A player fault gives the opponents the rally. A coach-distraction let cancels play since the last service and replays from the same score with the same server.
Three rules
“Hindrance” covers several different BWF decisions
The BWF Laws use the terms obstructed, distracted, and disrupted rather than creating a single fault called “hindrance.” Law 13.4.3 covers under-net invasion that obstructs or distracts. Law 13.4.4 covers preventing a legal stroke near the net. Law 13.4.5 covers deliberate player distraction.
Law 14.2.5 deals separately with a coach who disrupts play or distracts the opposing player. The wording is important: player interference under Law 13 is a fault, while qualifying coach interference under Law 14 is a let.
Under the net
Under-net invasion is a fault when it interferes
Law 13.4.3 makes it a fault when a player invades an opponent’s court under the net with racket or person so that the opponent is obstructed or distracted. The law does not say that every toe, racket tip, or follow-through crossing the vertical plane below the net is automatically a fault; the stated interference must be present.
Intent is not part of the wording of Law 13.4.3. An accidental under-net movement can therefore still be a fault if it obstructs or distracts the opponent. Ordinary movement entirely within a player’s own court is not under-net invasion.
Net interception
A defender cannot block an opponent’s legal stroke
Law 13.4.4 makes it a fault to obstruct an opponent by preventing that opponent from making a legal stroke where the shuttle is followed over the net. This works with Law 13.4.2: the striker must contact the shuttle on the striker’s own side, but the racket may then follow the shuttle across the net during the stroke.
A defender may take a normal position on the defender’s own side and try to intercept the shuttle after it crosses the net. The defender may not use racket or body position to prevent the opponent from making the legal stroke itself. The umpire reconstructs initial shuttle contact, each racket’s position, and the expected legal follow-through rather than treating every racket clash as automatic obstruction.
Player distraction
Deliberate shouting or gesturing during the rally is a fault
Law 13.4.5 makes it a fault when a player deliberately distracts an opponent by any action, with shouting and gestures given as examples. The list is not exhaustive, but the word “deliberately” is a real part of the test.
A spontaneous sound of effort, normal calling between doubles partners, ordinary court movement, or a deceptive badminton stroke is not automatically a distraction fault. It can become one when the umpire judges that the action was deliberately used to distract the opponent. Volume alone does not replace the need to assess purpose, timing, and context.
Legal deception
Disguising a shot is different from distracting a player
Badminton permits deception created through racket preparation, timing, body position, and shot choice. A hold-and-flick action or a disguised drop is directed at playing the shuttle and is not illegal merely because it sends the opponent the wrong way.
The boundary is crossed when an action is deliberately directed at distracting the opponent rather than executing or preparing a legitimate play. An umpire considers the whole action and its timing. A player cannot convert an ordinary feint into a fault simply by saying that it was distracting.
Coach interference
Coach-caused distraction produces a replay, not a point
Under Law 14.2.5, the umpire calls a let if, in the umpire’s opinion, play is disrupted or a player of the opposing side is distracted by a coach. Law 14.3 then cancels play since the last service and requires the player who served last to serve again.
This differs from deliberate distraction by an opposing player. The coach is outside the rally, so the Laws restore the rally rather than charge the player with a Law 13 fault. The score remains unchanged, and service does not transfer because of the let.
Advice window
Coaching is allowed between rallies, but the window closes
BWF Law 16.5.1 permits a player to receive advice only when the shuttle is not in play and until the players have taken up position to serve and receive. In practice, that allows brief courtside advice after one rally ends and before both sides settle for the next service.
Once the players have taken up those positions, coaching is no longer allowed. Advice is also prohibited while the shuttle is in play. A coach does not gain a longer window because the server pauses, and a player may not delay play in order to receive advice under Law 16.4.1.
Courtside conduct
BWF coaches must remain seated and avoid match communication
The BWF Instructions to Technical Officials in force 17 November 2025, Version 8.0, require courtside coaches to remain seated in their designated seats except during permitted intervals. A coach moving to another court must do so while the shuttle is not in play, and a coach may not move the designated chair without the Referee’s permission.
Those instructions also prohibit courtside coaches from communicating with opposing players, coaches, team officials, or on-court technical officials during the match, and from using an electronic device for any purpose. There must be no coach-caused distraction or disruption to play.
Intervals
Up to two accredited coaches may join each side
Under the current BWF technical-official instructions, no more than two accredited coaches may join each side on court during the permitted mid-game and between-game intervals. During a standard mid-game interval, the umpire calls “20 seconds” when 20 seconds remain, and the coaches must then leave the court.
The interval is not extra time beyond the Law 16 limits. Coaches must leave promptly so the players can resume, and advice cannot be used to delay play. Accreditation, seating, and access procedures belong to the governing competition and may be simpler in local events.
Umpire judgment
The official decides the observed facts in context
The umpire is in charge of the match, court, and immediate surrounds under Law 17. Whether an action prevented a legal stroke, whether a player acted deliberately, and whether a coach disrupted play or distracted an opponent are factual judgments based on the incident the umpire observed.
A player’s complaint is relevant information, but it does not automatically create a fault or let. The umpire considers timing, position, movement, sound, repetition, and the effect on play. Under Law 17, an official’s decision is final on the points of fact assigned to that official; an unsatisfied appeal on a question of law may be referred to the Referee before the next service is delivered.
Escalation
A rally ruling and disciplinary action are separate
Calling a Law 13 fault or Law 14 let decides the rally in front of the umpire. Repeated or serious behaviour can also require match-management action. The current BWF instructions require the Referee to be called immediately if a coach-distraction incident is repeated, and permit the Referee to remove a coach or team official from the field of play when necessary.
Player behaviour may separately fall under Law 16 if it becomes offensive, inappropriate, flagrant, repeated, persistent, or otherwise constitutes misconduct. A yellow-card warning, red-card misconduct fault, or possible disqualification follows the distinct Law 16 procedure; it should not be confused with the original obstruction or distraction call.
External interruption
Crowd noise does not create an automatic let
The specific coach let in Law 14.2.5 does not apply to every sound in a venue. Ordinary crowd noise, applause, and movement are part of many competition settings and do not automatically replay a rally.
A genuinely unforeseen or accidental event may support a let under Law 14.2.7, and circumstances outside the players’ control may require suspension under Law 16.3. The appropriate response depends on what occurred and the umpire’s assessment; there is no universal rule that any spectator sound must be treated as interference.
Worked calls
How common incidents are ruled
- Under-net foot interference: a player’s foot crosses under the net and causes the opponent to pull out of a movement. This is a Law 13.4.3 fault against the invading player.
- Blocked legal follow-through: a defender holds a racket so close that the opponent is prevented from completing an otherwise legal stroke after contacting the shuttle on the opponent’s own side. This is obstruction under Law 13.4.4.
- Racket clash without obstruction: the umpire reconstructs the stroke and racket positions. The sound of contact alone does not prove which player, if either, prevented a legal stroke.
- Deliberate shout: a player shouts to put the opponent off while the opponent is striking. If judged deliberate distraction, it is a Law 13.4.5 fault.
- Doubles call: partners call “mine” during normal play. That is not automatically a fault; the deliberate-distraction test still applies.
- Coach calls during a rally: the umpire judges that the opposing player was distracted. A let is called, the score is unchanged, and the last server serves again.
- Advice after a rally: a seated coach gives a short instruction before the players take up their next service positions. That falls within the Law 16.5.1 window if it causes no delay.
- Advice after players are ready: coaching continues after the server and receiver have taken position. The umpire stops the improper coaching and manages any delay or repeated conduct under the applicable procedure.
Common misunderstandings
Seven claims that need correction
- “Any hindrance is a let.” No. Player obstruction or deliberate player distraction is a fault; qualifying coach interference is a let.
- “Any noise by a player is a fault.” No. Law 13.4.5 requires deliberate distraction.
- “Every racket clash is obstruction.” No. The umpire must decide whether a player prevented an opponent from making the specified legal stroke.
- “Crossing under the net is always a fault.” Law 13.4.3 requires under-net invasion that obstructs or distracts the opponent.
- “Coaching is banned for the whole match.” No. Advice is allowed while the shuttle is not in play until the players take up position to serve and receive.
- “Coaches can talk until the server strikes.” No. The coaching window closes when the players take their service and receiving positions, before the service is delivered.
- “A coach’s shout awards the opponents a point.” The immediate Law 14.2.5 ruling is a let when its test is met; separate action against the coach may follow.
Competition scope
Local competitions may use different coach-management procedures
The fault and let principles on this page come from the BWF Laws of Badminton. The designated-seat, accreditation, electronic-device, and Referee-removal procedures come from BWF technical-official instructions for organised competition with appointed officials.
A national association, school, club, or recreational event may adopt the BWF Laws while using fewer officials or different courtside-access procedures. In a match without an umpire, Law 14 allows a player to call a let, but there is no neutral official to make the factual assessment. Players should identify the governing body and event rules before treating BWF tournament operations as universal local procedure.
Official references
Source material