The ultimate goal of saddle fit is to have the saddle that fits both the horse and rider, more importantly the horse.

There is no industry standard when it comes to tree sizes so different saddle brands will not fit the same and may vary among disciplines. So it's important to have some basic knowledge about saddle fitting.

There are many factors that come into play when checking the fit of your saddle on your horse. 

The 2 main factors are gullet width and bar angle.

Gullet Width: is often misunderstood.  Gullet width is the measurement under the fork between the side conchos.  Keep in mind this won't be entirely accurate as saddle makers determine gullet width on a bare tree.

A narrow gullet will sit higher on a horses wither vs a wide gullet will sit lower.

Bar Angleis often ignored.  Bar angle is basically self explanatory.  It's the angle of the bars on a saddle.  They need to match the angle of your horses back as closely as possible.

A narrow angle will make contact at the bottom of the bars but not the top and a wide angle will make contact at the top of the bars but not the bottom.

Tree Sizes

  • Quarter Horse Bars - Fit narrower western horses.  Gullet width of 5 3/4" - 6".
  • Semi-Quarter Horse Bars - Fit most of today's western horses.  Gullet width of 6" - 6 1/2".
  • Full Quarter Horse Bars - Fit wider western bodied horses.  Gullet width of 6 3/4" - 7".

The gullet width should be about the same width of the withers, approximately 2" below the top of the withers. Just remember, the main thing you need to know is, is your horse narrow, wide or in-between!

Approximate degrees (+/- 3 degrees):
86 degrees - narrow angle
90 degrees - wide angle
94 degree - extra wide angle
Other factors contributing to saddle fit.
Bar Flare:
Bar Slope:
Characteristics to take into consideration when fitting a saddle to your horse.
Shape of the horses back:
Length of the horses back: you don't want your saddle digging into your horses loins. 
Shape of the horses withers:
Shape of the horses shoulders:
Now it's time to take everything you've learned and check the saddle fit on your horse.
1. With your horse standing on level ground and squared up, place the saddle on it's back and slide it into place (often times this step is missed).  Often times, riders will place the saddle too far forward or too far back.  Which can cause saddle sores, restrict movement, and soreness.