Basketball referees use a standardised set of hand signals to communicate every call during a game — fouls, violations, shot values, timeouts, and substitutions. Understanding these signals lets you follow the game in real time without needing commentary. There are approximately 25–30 official signals used in NBA and FIBA basketball.

Referees communicate through hand signals because arenas are loud and players, coaches, and scorers' table officials all need to receive the same information simultaneously. A signal is universal and instant — no ambiguity, no mishearing.

Foul Signals

Personal Foul
Both fists raised above the head, clenched. This is the baseline foul signal. The referee then uses the number of fingers to indicate which player committed the foul (player number communication). The most common signal in any game.

Blocking Foul
Both hands placed on the hips. Indicates that a defensive player was not legally established in their position when contact occurred. One of the most contested calls in basketball — the difference between a block and a charge.

Charging Foul (Offensive Foul)
One closed fist punched forward from the chest, like a pushing motion. Indicates the offensive player made illegal contact by running into a defender who had established legal guarding position. Results in a turnover.

Holding Foul
One hand grips the opposite wrist. Indicates a player held another player illegally, restricting their movement without the ball.

Illegal Use of Hands
One hand slaps the wrist of the opposite hand. Indicates a player made contact with another player's hand or arm in a way that is not incidental. Common call on perimeter defence.

Pushing / Flagrant Foul
Both arms extended forward, palms outward — a pushing gesture. Indicates illegal contact with a push. For flagrant foul designation, the referee will signal the push and then signal "two free throws" or consult the review table.

Technical Foul
Both hands form a "T" shape — one hand vertical, one horizontal across it. Called for unsportsmanlike conduct, arguing with officials, illegal equipment, or bench violations. Results in one free throw for the opposing team and possession.

Double Foul
Both fists raised simultaneously, held at chest level. Indicates both teams committed fouls on the same play — typically simultaneous or offsetting fouls.

Violation Signals

Travelling
Both hands rotate around each other in a circular motion, as if rolling a ball forward. One of the most commonly signalled violations — called when a player takes too many steps without dribbling.

Double Dribble
Both hands move downward simultaneously, palms facing the floor, then stop. Called when a player dribbles the ball, stops, then dribbles again — or when a player dribbles with both hands at once. [→ See our full double dribble guide]

Ball Handling (Carrying)
The referee turns the hand over in a half-circle, palm up then rotating to palm down. Called when a player places their hand under the ball during a dribble and lifts or carries it rather than pushing it down.

Three Seconds Violation
Three fingers extended, held downward toward the lane. Called when an offensive player remains in the key (the paint) for three consecutive seconds. Resets every time the player exits the lane or a shot goes up.

Five Seconds Violation
Five fingers extended, then a chopping motion downward. Called when a player fails to inbound the ball, shoot a free throw, or advance the ball past half-court within the required time.

Eight Seconds (NBA / FIBA)
Both hands held out, eight fingers extended. Called when the offensive team fails to advance the ball from the backcourt to the frontcourt within 8 seconds (NBA/FIBA). High school and some leagues use 10 seconds.

Shot Clock Violation (24 Seconds)
One hand taps the top of the head. Indicates the offensive team failed to attempt a shot within the 24-second shot clock (NBA/FIBA). The 24 resets when the ball touches the rim or the possession changes.

Backcourt Violation
One arm extended, thumb pointing backward over the shoulder. Called when the offensive team, once having established the ball in the frontcourt, returns the ball to the backcourt.

Goaltending / Basket Interference
One hand held flat above the head, then a waving motion. Called when a player interferes with the ball on its downward arc toward the basket, while it is on the rim, or when a player reaches through the basket from below.

Kicking Violation
A kicking motion with one foot. Called when a player intentionally kicks the ball. An accidental contact is not a kick violation.

Lane Violation
Arms extended outward to the sides. Called during free throws when a player enters the lane before the ball touches the rim.

Shot Value Signals

Two-Point Field Goal
No specific signal — the referee simply points to the basket or raises two fingers briefly in some leagues. Two-point shots are the default.

Three-Point Field Goal (Attempt)
Before the shot is taken, the referee extends one arm with three fingers raised to indicate the shooter is behind the arc.

Three-Point Field Goal (Confirmed)
After a successful three-point attempt, the referee extends both arms above the head with three fingers on each hand, then swings both arms outward. This is one of the most visually distinctive signals in basketball.

Game Administration Signals

Timeout
One hand forms a "T" against the palm of the other hand — both hands forming a capital T at chest level. Signals a team timeout request has been granted.

Substitution
Both forearms crossed in front of the body at waist level, then the arms swing upward and outward alternately. Signals that a substitution is being made.

Start Clock
One arm sweeps downward in a chopping motion. Signals the shot clock or game clock to resume.

Stop Clock
One arm raised straight up, fist closed. Signals the clock to stop.

Stop Clock (for Foul)
One closed fist raised. Specifically used when calling a foul — signals the clock stops.

Bonus (Penalty Situation)
Referee holds up a closed fist, then extends a finger for each bonus free throw. If the fouled team is in the penalty/bonus, the referee signals the number of free throws to be awarded.

Why Do Referees Use Three Officials?

NBA and top-level FIBA games use three officials: a crew chief and two referees. The three-person crew allows each official to cover specific areas of the court (frontcourt, backcourt, and the paint) without trying to cover the entire floor. When a call is close or contested, officials can communicate quickly to make a joint decision. This is why you'll sometimes see two or three officials converging before signalling — they're confirming they saw the same thing.