What is a fault in tennis?
B · Beginner · Serving · 6 of 8A fault is a serve that does not count: it misses the service box, the server swings and misses or the server commits a foot fault by touching the baseline or the court before hitting the ball. After one fault the server gets a second serve. Two faults in a row is a double fault, and the receiver wins the point.
How it works
A serve is a fault if:
- it does not land in the correct service box;
- the server misses the ball when trying to hit it;
- the ball touches a permanent fixture, a singles stick or a net post before it lands;
- the ball touches the server or the server's partner, or anything they wear or carry;
- the server breaks the rules on where to stand;
- the server foot-faults.
A foot fault, during the service motion, is:
- changing position by walking or running (slight foot movements are allowed);
- touching the baseline or the court with either foot;
- touching the ground outside the imaginary extension of the sideline;
- touching the imaginary extension of the centre mark.
After a fault, the second serve is taken without delay from the same half of the court.
Tricky cases
Is it a foot fault if the server's foot lands inside the court after hitting the ball?
No. The rule applies during the service motion, which ends when the racket hits the ball.
The serve hit the net post and dropped into the right box. Is it good?
No. A serve that touches a net post or singles stick before landing is a fault.
The first serve was a fault, then the point was replayed for a let in the rally. First or second serve?
First serve. When a let is called in a rally, the whole point is replayed.
Why the rule exists
Two serves let players attempt a strong first serve while the second keeps the risk real. The foot-fault rule stops the server starting closer to the net.
Where it differs
| Where | What changes | Source |
|---|---|---|
| ITF rules | As above | L18, 19, 20, 23 |
| Singles | The server may not stand behind the strip between the singles and doubles sidelines; in doubles this is allowed | L18 Case 1 |
From the rule book
ITF Rules of Tennis 2026, Rules 16 to 20, 23 and 24 a. Checked 13 October 2026. Official document: ITF Rules of Tennis (PDF).