Swelling along the back, saddle sores, girth galls etc are all tell-tale signs of poor saddle fit. After riding and removing the saddle, uneven sweat patterns under the saddle pad can indicate an issue with saddle fit. These come about when the saddle is making uneven contact with your horse’s back.
Place your hand into the space between the saddle and your horse’s wither, using your fingers to measure the vertical space. The gap should fit no more than two fingers to two and a half fingers. If three or more fingers fit, the gullet is too narrow. If fewer than two fingers fit, the gullet is too wide.
A standard gullet measures 7 inches and is the most common measurement found in saddles described as having “full quarter horse bars”. Any gullet that measures larger than 7 inches is considered to be wide.
Semi-Quarter horse bars usually have a 6 1/4″ gullet, and Quarter Horse Bars usually have a 6 1/2″ to 6 3/4″ gullet. Designed to fit the average horse, one of these two widths will fit approximately 80% of horses comfortably. Full-Quarter horse bars usually have a 7″ gullet.
Measuring your Saddle Seat SizeYour MeasurementYour Saddle SizeLess than 16.5″15″ saddleBetween 16.5″ and 18.5″16″ saddleBetween 18.5″ and 20″16.5″ saddleBetween 20″ and 21.5″17″ saddle
You should be able to put one index finger under the cinch to your finger’s first joint. If you can reach in at the back of the cinch more than that, it’s probably too loose. If you can’t fit a finger in at all, it may be too tight.
When a saddle is too wide in the front, it can sink down over the withers. This takes the saddle out of balance by making the pommel lower than the cantle, which in turn carries more pressure over the front of the tree (at the withers/shoulders) than a saddle with a properly sized tree.
Place the saddle on the horse’s bare back (no pad). There should be two to three fingers space between the top of the wither and the gullet of the saddle. If you can fit your whole hand (vertically) between the bottom of the gullet and the wither, the tree is probably too narrow.