Handicapping 101
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Understanding Indexes and Handicaps


Why should I get an official USGA Handicap Index?

A USGA Handicap Index allows players of varying abilities to play golf with each other on equal footing. It represents a player’s potential playing ability and is portable so you can take around the world to thousands of courses.  In addition, GAM, USGA, and other tournaments often require a competitor have a USGA Handicap Index to participate.


How can I get and maintain a Handicap Index?

As a GAM member, you get access to a USGA Handicap Index as part of your membership. For information on posting scores and viewing your Handicap Index information click HERE

A Handicap Index is calculated by averaging the lowest 8 of the most recent 20 Score Differentials. To establish your first official USGA Handicap Index, you will need to post a minimum of three 18-hole scores (six 9-hole scores, or equivalent number of nine and eighteen hole scores).   The more scores you post, the more representative your index. To maintain a current index, you should continue to post all adjusted gross scores for rounds played under authorized formats and by the Rules of Golf.


The number of scores posted, determines the number of score differentials to use to Calculate your Handicap Index

Total Scores Posted

Number of Lowest Score Differentials to use



Lowest 1



Lowest 1



Lowest 1



Average of Lowest 2


7 or 8

Average of Lowest 2


9 to 11

Average of Lowest 3


12 to 14

Average of Lowest 4


15 or 16

Average of Lowest 5


17 or 18

Average of Lowest 6



Average of Lowest 7


20 +

Average of Lowest 8



What is the difference between a Handicap Index, a Course Handicap, and a Playing Handicap?

  • Your Handicap Index is the measurement of your demonstrated ability on a course of standard playing difficulty. This number is portable and can be turned in a Course Handicap at any tee with a valid Course and Slope Rating
  • Your Course Handicap is the number of handicap strokes a player receives, before handicap allowances, from a specific set of tees you are playing
  • Your Playing Handicap is your Course Handicap adjusted for any handicap allowances or differences in par between tees, and it represents the actual number of strokes the player gives or receives for the round being played.

The following shows how a Handicap Index is used to calculate a Course Handicap.

 Example: if you have a USGA Handicap Index of 17.2 and are playing on a course with a:

  • Slope Rating of 127, a Course Rating of 70.5 and a par of 72; the Course Handicap is 18
  • Slope Rating of 118, a Course Rating of 68.9 and a par of 72; the Course Handicap is 15

Because of the difference in the ratings, you will a different course handicaps for each course. Use the Course Handicap Calculator found at all GAM member courses or  take your:

Your Course Handicap on Different Courses


Handicap Index  X (Slope Rating/113) + (Course Rating – Par) = CH
(Handicap is rounded to nearest whole number)


Using the example above: 17.2 X (127/113) + (70.5-72) = 18


Your Course Handicap =

Handicap Index X (Slope Rating/113) + (Course Rating – Par) = CH
(Handicap is rounded to nearest whole number)


Using the example above: 17.2 X (118/113) + (68.9-72) = 15