GUIDES · BETSLIP DOCTOR
What happens when a putt accidentally hits another ball on the putting green?
Under the joint R&A/USGA 2023 Rules of Golf, the result depends on whether the other ball was at rest or still moving. In stroke play, a two-stroke penalty applies when a putt hits a ball at rest on the green and both balls were on the green before the stroke. A retained Rule 11 clarification requires replay when a putt is known or virtually certain to hit another ball moving on the green.
For Golfers who want to know whether a putt that hits another ball on the green must be replayed or carries a penalty. · Updated
A ball at rest has a narrow stroke-play penalty
An accidental hit normally carries no penalty and the moving ball is played as it lies. The exception is a stroke made from the putting green in stroke play that hits another ball at rest on the putting green, when both balls were on the green before the stroke. The player who made the stroke gets the general penalty: two penalty strokes.
The exception turns on all of those facts: stroke play, a ball at rest, and both balls on the putting green before the stroke. It does not apply just because two golf balls touch.
The ball that was originally at rest has a separate procedure. If it is known or virtually certain that the other ball moved it, that ball must be replaced on its original spot, estimated if unknown, without a movement penalty. This replacement duty is separate from playing the striking ball as it lies and applying the striking player’s stated stroke-play penalty.
Another moving ball can require a replay
The current Rule 11 clarification addresses a different event: a ball played from the putting green accidentally hits another ball that is itself moving on the putting green. If that contact is known or virtually certain, the player must replay the stroke from the spot where it was made, using Rule 14.6.
This clarification was added in January 2024 and appears in the R&A and USGA clarification document updated October 2, 2026. The document says there were no new clarifications for October; that does not remove this retained earlier clarification.
Check what was moving before applying the rule
Before deciding what to do, determine whether the other ball was at rest or moving, whether each ball was on the green before the stroke, and whether the collision with a moving ball is known or virtually certain. A ball moved by natural forces raises a different question under other Rules; do not treat it as the same situation as a putt colliding with another ball in motion.
Two fictional putt collisions
In stroke play, Taylor putts while both Taylor’s ball and another ball are at rest on the putting green. The putt hits and moves the other ball; the specific two-stroke exception applies to Taylor, and Taylor’s ball is played as it lies. Because it is known that the collision moved the ball originally at rest, that ball’s owner replaces it on its original spot, estimating the spot if unknown. In a separate fictional case, Lee putts while another ball is still rolling on the green. The collision is known or virtually certain, so Lee replays the stroke from the previous spot. These examples do not decide an actual competition ruling.
Related questions
Does the two-stroke penalty apply if the other ball was moving?
The two-stroke exception described in Rule 11.1a is for a ball at rest. A separate retained clarification requires replay when a putt is known or virtually certain to hit another ball in motion on the green.
Does the retained moving-ball clarification still apply after the October 2026 update?
Yes. The October 2, 2026 clarification document says there were no new clarifications for October and still includes the 11.1b(2)/1 clarification added in January 2024.