A jump ball is a method used to begin or resume play in basketball. It is used to give both teams an equal chance at possession. The jump ball is used to start games and, in the professional game, when the ball is possessed by two opposing players at the same time. The players participating in the jump ball are not allowed to grab the ball. Instead, they must tap and redirect the ball in the direction of a teammate using one hand.

In the NBA, WNBA, and competitions operated by Euroleague Basketball, a jump ball occurs at the start of the game (called the opening tip or opening tip-off), the start of any extra period (tip-off), to settle special situations where penalties cancel out and neither team is previously entitled to the ball, and to settle any held balls. Held balls occur when two opposing players both lay equal claim to the ball, and after trying to wrestle it from each other, end up in a stalemate.

However, most competitions other than the NBA, WNBA, and Euroleague Basketball use the alternating possession rule to settle all jump ball situations after the opening tip. This uses a possession arrow on the scorekeepers table. Whenever such a jump ball situation occurs, possession of the ball is awarded to the team that is moving in the direction of the possession arrow on offense. The arrow then swaps to point to the other team.

In basketball, a jump ball means that play is beginning, and a player from each team will jump up, attempting to gain possession of the ball after an official tosses the ball up between them. The jump ball is executed by tapping the ball after it reaches its highest point.