A tennis point starts with a serve that must land in the service box diagonally opposite the server. Players then hit the ball back and forth over the net, and each shot must be returned before the ball bounces twice and must land inside the opponent’s court. Points are scored love, 15, 30, 40 and game, with deuce at 40-40. A set is usually won by the first player to reach six games with a lead of two, with a tiebreak commonly played at 6-6, and matches are typically best of three or best of five sets. This guide explains the scoring system, serving rules, faults and lets, how points are won and lost, changing ends, singles and doubles differences, time rules, line calls and the most common rules mistakes.
Rulebook note: The rules summarized here come from the ITF Rules of Tennis, the international standard. Tours, national federations such as the USTA, schools, colleges and leagues may add their own regulations or use alternative formats, such as no-ad scoring, match tiebreaks, different time limits and coaching rules. Always check the current rules for your event.
Key rules at a glance
| Rule | Summary |
|---|---|
| Scoring | Love, 15, 30, 40, game; deuce at 40-40, win by two points |
| Sets | First to 6 games with a two-game lead; tiebreak commonly at 6-6 |
| Matches | Best of three or best of five sets |
| Serve | Two attempts; stand behind the baseline; land in the diagonal box |
| Let | Serve touches the net and lands in; the serve is replayed |
| Foot fault | Touching the baseline or court with either foot before hitting the serve |
| In or out | A ball touching any part of a line is in |
| Changing ends | After odd-numbered games in each set; every six points in a tiebreak |
Scoring
In each game, the first point won is called 15, the second 30 and the third 40. Winning the next point wins the game, unless both players reach 40. At 40-40, called deuce, a player must win two points in a row. The player who wins the point after deuce has the advantage, and if they win the next point they win the game. If they lose it, the score returns to deuce. Zero is called love. The server’s score is announced first. A set is won by the first player to win six games with a lead of at least two, such as 6-4. At 5-5, a player must reach 7-5. At 6-6, most events play a tiebreak, in which the first player to seven points with a two-point lead wins the set 7-6.
Serving rules
The server stands behind the baseline, between the imaginary extension of the center mark and the sideline, and serves diagonally into the opponent’s service box. The first point of each game is served from the right side, called the deuce court, and the server alternates sides after each point. The server has two attempts. A serve that misses the box, hits the net and does not go over, or is otherwise not legal is a fault. Two faults in a row is a double fault, and the server loses the point. Players alternate serving games throughout the set.
Foot faults
A foot fault occurs if, during the service motion, the server touches the baseline or the court inside it with either foot, touches the area outside the imaginary extension of the sideline, or changes position by walking or running. The server may jump, as long as neither foot touches the line or court before the racquet hits the ball. A foot fault counts as a fault.
Lets
Under the ITF rules, a serve that touches the net, strap or band and then lands in the correct service box is a let, and that serve is replayed without counting as a fault. A let can also be called during a point if play is interrupted, for example if a ball rolls onto the court from another court, and the whole point is replayed. Some formats, particularly in some college and league play, use no-let rules where a serve that clips the net and lands in stays in play, so check the format in use.
How a point is won or lost
You lose the point if:
- The ball bounces twice on your side before you hit it.
- You hit the ball out of the court or into the net.
- You hit the ball before it has crossed the net to your side.
- You, your racquet or anything you are wearing or carrying touches the net, net posts or your opponent’s side of the court while the ball is in play.
- The ball touches you or your clothing, rather than your racquet.
- You deliberately carry, catch or hit the ball twice.
- You throw your racquet and hit the ball with it.
- You double fault when serving.
A ball that hits the net during a rally and goes over into the correct court is in play. A ball that hits the net post or singles stick and then lands in the correct court is also good. You may follow through over the net after hitting the ball, as long as you made contact on your own side and did not touch the net.
Changing ends
Players change ends after the first, third, fifth and every subsequent odd-numbered game of each set. They also change ends at the end of each set if the total number of games in that set is odd. In a tiebreak, players change ends after every six points. Rest periods are set by the rules, with the ITF allowing up to 90 seconds at changeovers, except after the first game of a set, and up to 120 seconds at the end of each set. Events may use different limits.
Time between points
The ITF rules set a maximum time between points, often 25 seconds, and many events enforce it with a serve clock. Players who exceed the time may receive warnings and penalties under the event’s code of conduct. Players also get a short warm-up before the match, commonly around five minutes, although this varies.
Singles and doubles differences
Singles uses the inner sidelines, while doubles uses the outer sidelines, which adds the doubles alleys to the court. The service box is the same in both. In doubles, teams alternate serving games, and partners take turns serving in the order they choose at the start of each set. Each receiver returns serve from the same side throughout the set. Partners can stand anywhere on their side during points, but only the correct receiver may return the serve.
Line calls and officials
In many recreational and junior matches without an umpire, each player calls the lines on their own side of the court. The general principle is that if you are not sure a ball was out, you give your opponent the benefit of the doubt and call it in. Calls should be made promptly and clearly. In officiated matches, line judges, chair umpires or electronic line-calling systems make the calls, depending on the event.
Step-by-step: playing your first match by the rules
- Agree on the format: sets, tiebreak and scoring type.
- Decide who serves first, often by spinning a racquet.
- Serve from the deuce court to start each game.
- Announce the score before each serve, server’s score first.
- Call lines fairly on your side.
- Change ends after odd-numbered games.
- Play a tiebreak at 6-6 if agreed.
- Shake hands at the end of the match.
Common rules mistakes
- Serving from the wrong side of the court.
- Forgetting to change ends after odd games.
- Calling balls on the line out.
- Touching the net during a point.
- Replaying a serve that touched the net and missed the box, which is a fault.
- Not announcing the score, leading to disputes.
- Assuming every event uses the same format.
Frequently asked questions
Why is tennis scored 15, 30, 40?
The origin is uncertain. Several historical explanations exist, but none is confirmed, and the system has simply been kept by tradition.
Is a ball on the line in or out?
It is in. Lines are part of the court, so a ball touching any part of the line is good.
What happens if the serve hits the net and lands in?
Under standard rules it is a let and the serve is replayed. Some formats use no-let rules, where the ball stays in play.
