The simplicity and the hidden complexity of this tie-breaker is revealed
Countback is a way to separate tied players after the conclusion of a competition. It does not involve playing any more holes, only number crunching by the competition secretary.
The way countback is calculated can vary according to club rules. or the rules of a particular competition. But here follows an explanation of the standard method.
In an 18-hole event, ties are separated by the best score over the final nine holes. These are the final holes on the standard scorecard. Thus they are the course’s 10th to 18th holes rather than the final nine holes a player might have played, which may be different if it was a shotgun or two-tee start.
If the best score for the last nine holes does not separate out a winner, then the final six holes are used, and, if that still fails to provide a definitive outcome, the final three holes. If a tie still persists then the score on the final hole is used.
In multi-round events the last 18 holes are first used for countback. If this cannot separate a tie, then the countback method for 18-hole events is then applied, as described above.
In a Stableford Competition the point scores for each hole is used and totalled, and as such is nice and straightforward. But in a handicap stroke competition calculating countback can get a wee bit more complicated.
Rather than use the net scores on each hole, standard practise is to deduct handicaps in proportion. Thus for countback on the last nine holes half the handicap is applied.
As most courses alternate the stroke indexes between the front and back nines, this rarely has a noticeable effect on a back-nine countback. But, when it gets down to a third of the handicap for the final six holes and a sixth for last three holes, players can then start to get shot on parts of the course where they do not normally get them.