5.1b For a 9-hole Score

If a player submits a 9-hole score, an 18-hole Score Differential must be created by combining two 9-hole Score Differentials.

A 9-hole Score Differential is calculated as follows using 50% of the playing conditions calculation (PCC) adjustment for the day:

= (113 ÷
9-hole Slope Rating)
x (9-hole adjusted gross score
9-hole Course Rating
(0.5 x PCC adjustment))


  1. A 9-hole Score Differential remains unrounded until after it has been combined with a second 9-hole Score Differential and an 18-hole Score Differential is calculated.
  2. For the calculation of a 9-hole Course Handicap, see Rule 6.1b For a 9-hole Round.
  3. An 18-hole PCC adjustment ranges from -1.0 to +3.0 (see Rule 5.6 Playing Conditions Calculation).

An 18-hole Score Differential is then created by either:

Note: An uncombined 9-hole score will be discarded when it becomes older than the twentieth Score Differential in the scoring record.