- Catching a fly ball, line drive, or third strike before they touch the ground
- Touching a base while in possession of the ball to record a force out, appeal play, or retire the batter at first base
- Tagging a runner with the ball, or with a hand or glove holding the ball, while the runner is not safely touching a base
Putouts are an essential part of baseball accounting. Since each batter must eventually be put out, score, or be left on base, the official scorer can "prove" a box score by showing that a team's plate appearances is equal to the sum of its runs, runners left on base, and the opposing team's putouts. That makes it important to record a putout for every player retired, even if the fielder took no concrete action to record the out. In such instances, credit is given as follows:
- The catcher receives a putout if the batter is automatically out for batting illegally, bunting foul for a third strike (unless the foul ball is caught on the fly), striking out with first base occupied and less than two out (even if the catcher fails to catch the ball), being touched by his own batted ball, batting out of order, or refusing to advance to first on a walk.
- The catcher also receives a putout if a runner fails to advance from third base with an apparent winning run.
- If the batter is out for an uncaught infield fly, a putout is credited to the fielder who could have caught the fly.
- If a runner is out for being touched by a batted ball, the closest fielder receives a putout.
- If a runner is out for running out of the baseline to avoid a tag, the fielder whose tag he avoided is credited with a putout.
- If a runner is out for passing another runner, the nearest fielder gets a putout.
- If the batter or a runner is out for interference, the fielder he interfered with is credited with a putout. If the fielder is in the act of throwing the ball, the putout is credited to the fielder he was throwing to, and the fielder is credited with an assist.
- If the batter is out because of interference by a preceeding baserunner, the first baseman is credited with a putout.
- If a runner is out for running the bases in reverse order, the assist is credited to the fielder covering the base he started from.