What Happens If Your Golf Ball Hits Another Ball on the Green?

Rulings by situation

What happened	Penalty to you	Your ball	The other ball	Rule
Stroke play: putt from the green hits a ball at rest on the green	2 strokes	Play it as it lies	Replaced, no penalty	11.1a Exception, 11.1b(2), 9.6
Match play: same situation	None	Play it as it lies	Replaced, no penalty	11.1a, 11.1b(2), 9.6
Chip or pitch from off the green hits a ball on the green	None	Play it as it lies	Replaced, no penalty	11.1a, 11.1b(1), 9.6
Putt from the green hits another ball that is also moving on the green	None	Replay the stroke from the original spot	If it was also played from the green, the same clarification applies and that stroke is replayed too; if it was played from off the green, it is played as it lies	Clarification 11.1b(2)/1, 11.1b(1)
Players agree to leave a ball near the hole as a backstop, and a player plays with it there (stroke play)	2 strokes to each player who agreed	Not covered by this rule	Not covered by this rule	15.3a

Sources: Rule 11, Rule 9.6, Rule 15.3, Clarification 11.1b(2)/1.

Why the penalty applies only on the green

Rule 11.1a says that when a ball in motion accidentally hits a person or outside influence, there is no penalty to any player. The exception is a ball played on the putting green in stroke play: if the ball in motion hits another ball at rest on the green, and both balls were on the green before the stroke, the player gets the general penalty. The general penalty is two strokes in stroke play and loss of the hole in match play, but this exception is written for stroke play only, so match play has no penalty.

If you chip from the fringe or fairway and hit a ball on the green, the exception doesn't apply, because your ball wasn't on the putting green before the stroke.

What to do next

1. Your ball: Rule 11.1b(2) says a ball played from the green that accidentally hits an outside influence is normally played as it lies. A ball at rest is listed as one of the things that does not trigger a replay.
2. The other ball: Rule 9.6 says when an outside influence, including another ball, moves a player's ball at rest, there is no penalty and the ball must be replaced on its original spot, estimated if not known.
3. Score it: in stroke play, add two penalty strokes to your score for the hole if both balls were on the green before the stroke.

The owner of the moved ball should replace it before playing. Playing it from where it was knocked to is a wrong-place breach under Rule 9.6, carrying the general penalty.

If your putt hits something other than a ball

The two-stroke penalty is only for hitting a ball at rest. Rule 11.1b(2) covers the other things a putt from the green can hit (Rule 11):

Your putt from the green hits...	What you do	Penalty
A ball-marker	Play your ball as it lies	None
You, or the club you just used	Play your ball as it lies	None
Another person on the green (not you, not someone attending the flagstick)	Replay the stroke from the original spot	None
An animal on the green, other than an insect or similar loose impediment	Replay the stroke	None
A movable obstruction on the green, such as a rake or someone's glove	Replay the stroke	None
The flagstick or the person attending it	Covered by Rule 13.2b(2), not Rule 11	Depends on the case

If you are supposed to replay the stroke and don't, the stroke counts and you get the general penalty (Rule 11).

How to avoid it

Rule 15.3 gives every player the tools:

• If you think another player's ball on the green might help anyone, for example as a backstop near the hole, you can mark and lift your own ball or require the other player to mark and lift theirs (15.3a).
• If you think another player's ball might interfere with your play, including being on your line, you can require them to mark and lift it (15.3b).
• In stroke play, a player asked to lift may choose to play first instead.

Players who agree to leave a ball in place to help someone, when that player then plays with the ball left there, each get the general penalty in stroke play (15.3a).

Which edition applies

These are the 2023 Rules of Golf, published jointly by The R&A and the USGA. The clarification on two moving balls was added in January 2024. The R&A's site shows them as the current rules as of October 2026.