Fault
A breach of the rules; in racket and net sports specifically, an illegal or failed service.
Definition
In its broadest sense a fault is any infringement of the rules, but in racket and net sports it most often means a service that fails to meet the requirements — a serve that misses the correct box, or a foot fault where the server steps on or over the line before striking the ball. In tennis a single service fault gives the server a second attempt; missing both is a double fault and loses the point.
The meaning shifts by sport. In volleyball a 'fault' is any action that breaks the rules — a lift, a net touch, or a positional error — and awards a point to the opponent. In athletics field events, an invalid attempt such as overstepping the take-off board is recorded as a foul or 'no jump,' expressing the same idea of an illegal attempt.
Meaning by sport
This term is used differently across sports:
- Tennis
- An illegal or missed serve; two faults on the same point is a double fault.
- Badminton
- A service or rally infringement that ends the rally in the opponent's favour.
- Volleyball
- Any rule violation, such as a lift or net touch, that loses the rally.
- athletics
- An invalid field-event attempt, such as overstepping the take-off board ('no jump').
Where you’ll hear “fault”
Sports that use this term:
Tennis
A singles or doubles racquet sport that blends agility, strategy and stamina on court.
Badminton
A fast indoor racquet sport played with a shuttlecock that rewards agility and touch.
Volleyball
A non-contact team sport of rallies, jumps and teamwork — indoors or on the beach.
Padel
A sociable, doubles-first racquet sport played in an enclosed court where the walls stay in play.
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Rules
- Foot faultA serving fault called when the server's foot touches the baseline or court before striking the ball.
- Touching the netA net-play rule that penalises a player for contacting the net during a rally in net-divided sports.
- The padel servePadel's underarm serve, set out exactly — the bounce before the strike, the waist-height limit, where the server's feet must be, and the wire-mesh fault that has no tennis equivalent.
- LetA call that stops a point and has it replayed without penalty, used across several racket sports.
- Badminton serve rulesThe rules for how a badminton serve must be delivered and where it must land.
Skills Academy
Skills
Officiating
- Line JudgeA boundary-line official who calls whether the ball or player is in or out and flags foot faults, working under the head referee across many sports.
- UmpireA match official who rules on lines, serves and dismissals in racket, bat-and-ball and net sports such as tennis, cricket and baseball — and, in racket sports, also keeps the running score.
Facilities
- Badminton courtA rectangular indoor court, divided by a high net, on which badminton is played as singles or doubles.
- Tennis courtA rectangular marked court, divided across the middle by a net, where tennis is played as singles or doubles.
- Padel court dimensionsThe exact size and markings of a padel court under FIP rules — the 10 by 20 metre rectangle, the service lines, the line width, and the free height the rules require above it.
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How this page is maintained
- Content type
- Term
- Provenance
- Tier A — evergreen educational
- Verified external sources
- 0
- Content updated
- 2026-09-01
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