Tennis (ITF) — Official Rules

The court is a rectangle 23.77 m (78 ft) long. For singles it is 8.23 m (27 ft) wide; for doubles it is 10.97 m (36 ft) wide. The end lines are the baselines and the side lines are the sidelines. Two service lines are drawn 6.40 m (21 ft) from each side of the net, parallel to it; the area between each service line and the net is divided into two equal service courts by the centre service line. Each baseline is bisected by a centre mark 10 cm (4 in) long. All measurements are made to the outside of the lines, which must contrast clearly with the surface.

The net divides the court across the middle, suspended from a cord or cable passing over two net posts 1.07 m (3½ ft) high. The net height is 0.914 m (3 ft) at the centre, where it is held down by a white strap; a white band covers the cord and the top of the net. For doubles, the centres of the net posts are 0.914 m (3 ft) outside the doubles court on each side. When a doubles net is used for singles, it is supported at 1.07 m by two singles sticks placed 0.914 m outside the singles court. Net posts may not exceed 15 cm square/diameter; singles sticks 7.5 cm.

A ball approved under the Rules of Tennis must conform to Appendix I. The standard Type 2 (medium) ball has a mass of 56.0-59.4 g (1.975-2.095 oz), a diameter of 6.54-6.86 cm (2.57-2.70 in), a rebound of 135-147 cm when dropped, and is white or yellow. Three speed types (Type 1 fast, Type 2 medium, Type 3 slow) and graded Stage 1 (Green), Stage 2 (Orange) and Stage 3 (Red) balls exist for surface pace and for 10-and-under tennis. If a ball breaks during play the point is replayed; a merely soft ball is not replayed.

A racket consists of a frame and string(s); the hitting surface must be flat with a pattern of crossed strings, generally uniform and no less dense at the centre. The frame shall not exceed 73.7 cm (29.0 in) in overall length and 31.7 cm (12.5 in) in overall width; the hitting surface shall not exceed 39.4 cm (15.5 in) long and 29.2 cm (11.5 in) wide. No energy source or device that could change the racket's playing characteristics may be built in or attached; only approved Player Analysis Technology and wear/vibration/weight devices are allowed. A player may not use more than one racket at a time.

A standard game is scored with the server's score called first: no point = "Love", first point = "15", second = "30", third = "40", fourth = "Game". If each player/team has won three points, the score is "Deuce" (40-40).

After "Deuce", the player/team who wins the next point has "Advantage". If that same player/team wins the next point they win the "Game"; if the opponent wins it, the score returns to "Deuce". A player/team must win two consecutive points immediately after Deuce to win the game.

Under the approved "No-Ad" scoring method, the game is scored Love/15/30/40, but at Deuce a single deciding point is played: the receiver chooses to receive from the right or left court (in mixed doubles the player of the same gender as the server receives), and the winner of that point wins the game. No-Ad scoring is widely used in doubles, college, and many recreational/tour formats to shorten matches.

There are two main methods of scoring a set, and the method used must be announced in advance. In an "Advantage Set" the first player/team to win 6 games with a margin of two wins the set, continuing until that margin is achieved. In a "Tie-break Set" the same applies, except that at six games all a tie-break game is played. If a Tie-break Set method is used, the event must also announce whether the final set is played as a Tie-break Set or an Advantage Set.

A tie-break game is played at 6 games all (in a Tie-break Set). Points are scored "Zero", "1", "2", "3"…; the first player/team to 7 points with a margin of two wins the game and the set (continuing until the margin is reached). The player due to serve serves the first point; thereafter players serve alternately for two points each, changing ends after every six points. The player who served first in the tie-break receives in the first game of the next set.

A match is played to the best of 3 sets (win 2 sets) or to the best of 5 sets (win 3 sets). Best-of-three is standard for most professional events; best-of-five is used in the men's singles main draws of the Grand Slams and historically in Davis Cup ties.

Appendix VI provides approved deciding-set alternatives. A Match Tie-break to 7 points or 10 points (margin of two) may replace the deciding final set when the match is one set all (or two-all in best-of-five). A Final-Set Tie-break to 10 points may be played at 6 games all in the final set. Since 2022 all four Grand Slams use a 10-point tie-break at 6-6 in the final set (margin of two) under the Grand Slam Board rules; many tour events use a 10-point match tie-break for deciding doubles sets.

The choice of ends and of being server or receiver in the first game is decided by a toss before the warm-up. The winner of the toss may choose to be server or receiver (the opponent then chooses the end), or choose the end (the opponent then chooses to serve or receive), or require the opponent to choose.

Players change ends at the end of the first, third and every subsequent odd game of each set, and at the end of each set unless that set has an even total number of games (in which case they change after the first game of the next set). During a tie-break game players change ends after every six points.

At the end of each standard game the receiver becomes the server and vice versa. In doubles, the team serving in the first game of a set decides which partner serves; the opponents decide before the second game; thereafter each player's partner serves in the corresponding later games, the rotation continuing to the end of the set. When serving, the server stands behind alternate halves of the court, starting from the right in every game.

Immediately before the service motion the server must stand at rest with both feet behind the baseline, within the imaginary extensions of the centre mark and sideline. The server then releases the ball by hand in any direction and strikes it with the racket before it hits the ground. The service motion is completed at the moment the racket hits or misses the ball. The service must pass over the net and land in the service court diagonally opposite before the receiver returns it.

During the service motion the server shall not: (a) change position by walking or running (slight foot movements are allowed); (b) touch the baseline or the court with either foot; (c) touch the area outside the imaginary extension of the sideline; or (d) touch the imaginary extension of the centre mark. A breach is a "Foot Fault" and counts as a service fault. The server may have one or both feet off the ground.

The service is a fault if: the server breaks the service/serving/foot-fault rules; misses the ball when trying to hit it; the ball touches a permanent fixture, singles stick or net post before hitting the ground; or the ball touches the server, the server's partner, or anything they wear or carry. After a first-service fault the server serves again from the same half. If the second service is also a fault, it is a "Double Fault" and the server loses the point.

The service is a let if the ball touches the net, strap or band and is otherwise good (or, after touching them, touches the receiver or partner before bouncing), or if the ball is served when the receiver is not ready. On a service let that particular service is replayed, but a service let does not cancel a previous fault.

In all cases when a let is called, the whole point is replayed — except when a service let is called on a second service, in which case only that second service is replayed (the player still has only one service remaining). For example, if a stray ball rolls onto court after a first-service fault, a let is called and the player is entitled to a first service again.

Unless a fault or a let is called, the ball is in play from the moment the server hits it and remains in play until the point is decided. A ball that touches a line is regarded as touching the court bounded by that line (i.e. it is good/in).

A player loses the point if, among other things: they serve two consecutive faults; fail to return the ball before it bounces twice; return it so it lands outside the correct court or hits a permanent fixture before bouncing; the receiver returns the service before it bounces; the player deliberately carries/catches the ball or touches it with the racket more than once; the player, racket or anything worn touches the net, posts, or the opponent's court while the ball is in play; the player hits the ball before it has passed the net; or the ball in play touches the player or anything worn (except the racket).

It is a good return if the ball passes over or around the net (including outside the posts, above or below net height) and lands in the correct court, even if it touches the net, posts, cord, strap or band on the way; if a ball that has bounced in court spins/blows back over the net and the player reaches over to play it back (without breaking Rule 24); if the racket passes over the net after the ball has been struck on the player's own side; or if the ball in play hits another ball lying in the correct court.

If a player is hindered by a deliberate act of the opponent, that player wins the point. If the hindrance is due to an unintentional act of the opponent or something outside the player's control (not a permanent fixture) — for example a ball in play striking a bird — the point is replayed. An unintentional double hit is not a hindrance.

When an error in respect of the Rules is discovered, all points already played stand. Specific corrections apply: a player serving from the wrong half is corrected immediately (a fault already served stands); players at the wrong ends are corrected and a fault served before discovery does not stand; a player serving out of turn is corrected as soon as discovered, but if a game is completed first the altered order stands. Errors in starting the wrong set type (Advantage/Tie-break/match tie-break) are corrected only if one point has been played, otherwise the set continues under defined rules.

Play should be continuous. A maximum of 25 seconds is allowed between points (a serve clock enforces this on tour). At a change of ends a maximum of 90 seconds is allowed, except that after the first game of a set and during a tie-break play is continuous and ends are changed without rest. At the end of each set there is a set break of up to 120 seconds. The maximum time runs from the end of one point until the next service is struck.

The warm-up is a maximum of 5 minutes. No extra time is given to recover condition, but a player with a treatable medical condition may take one medical time-out of 3 minutes for that condition. A limited number of toilet/change-of-attire breaks may be allowed if announced in advance. Event organisers may allow a rest period of up to 10 minutes, taken after the 3rd set in a best-of-five match or after the 2nd set in a best-of-three match.

"Coaching" is advice or instruction of any kind by any means. Off-Court Coaching may be permitted by the sanctioning body in events played under the Rules of Tennis — a notable liberalisation now adopted across the ATP, WTA and Grand Slam tours. On-Court Coaching is only permitted in team events with an on-court captain. Coaching is never permitted during the playing of a point, and is subject to Appendix IV (brief, discreet, verbal at the same end or by hand signals).

Where officials are appointed (Rule 28 / Appendix VII), the chair umpire is the final authority on all questions of fact and may overrule a line call where clearly mistaken. The chair umpire applies the Point Penalty / Code of Conduct procedures, the time rules, and may suspend or default a player. Line umpires, the net umpire and ball persons assist under the chair umpire's authority. Their recognised positions are permanent fixtures.

Electronic Line Calling Live (ELC Live) — the single biggest 2024-2026 officiating change — automatically calls every "out"/"fault" in real time. From 2025 it is used across the entire ATP Tour and at three of the four Grand Slams (Australian Open, Wimbledon, US Open), replacing human line judges. The French Open (Roland-Garros) is the notable exception, retaining human line judges on its clay courts. Under ELC Live there are no player challenges — the electronic call is final. The ITF maintains a list of classified ELC systems.

At events that still use human line judges with electronic review (rather than ELC Live), the legacy Hawk-Eye challenge system applies: each player gets 3 unsuccessful challenges per set, plus one additional challenge in a tie-break; a successful challenge is not deducted, and the allowance resets each set. The electronic review decision is final. This is a tournament regulation, not part of the ITF Rules of Tennis, and is being phased out in favour of ELC Live.

Tour/Grand Slam Codes of Conduct (ATP/WTA/ITF) — layered on top of the Rules of Tennis — list code violations such as audible/visible obscenity, ball abuse, racket abuse, verbal/physical abuse, unsportsmanlike conduct, coaching (where not permitted) and time violations. Penalties escalate on a Point Penalty Schedule: first offence = Warning, second = Point Penalty, third = Game Penalty, and further serious offences = Default. Aggravated conduct may be defaulted without the full progression.

Failing to serve or be ready within the 25-second limit between points is a Time Violation. Under the tour Code, the server's first time violation is a Warning and each subsequent one a Point Penalty (loss of first serve / point); for the receiver, repeated delays incur point penalties. The serve clock makes the 25-second limit visible to players and spectators.

A match ends other than by normal completion when a player retires (unable to continue, e.g. injury), is defaulted (disqualified for conduct or rule breach), or wins by walkover (opponent fails to start). In each case the opponent is credited with the win and the score stands as played up to that point.

Wheelchair tennis follows the ITF Rules of Tennis with key exceptions. Under the two-bounce rule, the wheelchair player may let the ball bounce twice and must return it before the third bounce; the second bounce may be inside or outside the court boundaries. The wheelchair is considered part of the player's body, so all body rules apply to it. In matches between a wheelchair and an able-bodied player, the wheelchair player gets two bounces and the able-bodied player one.

Before serving the wheelchair player must be stationary and is allowed one push before striking the ball, and must not let any wheel touch any area other than behind the baseline within the centre-mark/sideline extensions. A player loses the point if they fail to return before the third bounce, use any part of the feet/lower extremities against the ground or a wheel while serving/striking/turning/stopping during play, or fail to keep one buttock in contact with the seat when contacting the ball. Quad players may use a modified service if conventional serving is impossible.