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Where should you measure the gullet?

The only measurement commonly mentioned about how the western saddle might fit the horse is the gullet width. We must ensure that the front of the tree fits and that the whole tree follows the contours of the horse’s back. There are hundreds of variations in equine backs; you must measure to pick the tree best suited for your horse. Then you need to communicate those measurements to the saddle maker or the western saddle shop. Quantifying these into numbers and comparing the various offerings is difficult when there is no standard sizing.


How do you measure what size western saddle you need?

Western saddle seats are typically measured from the cantle front to the fork’s back edge. However, if the fork or cantle angle or height is changed, the western saddle seat size varies unnecessarily; when riding, we rarely make contact with any of those surfaces.

thigh size
Seat Size via thigh length

A better method is to measure the width of your thigh where it lays across the western saddle. To calculate thigh width, measure the circumference of the thickest part of your thigh, multiply it by 3.14, add an inch or so then compare it to a known saddle.

The western saddle tree is unquestionably the most crucial when asking, “Does the tree fit the shape of my horse’s back?” The military was the first customer of the saddle manufacturing industry, where each saddle was handcrafted and individually fitted for each horse. Nowadays, the majority of saddles are mass-produced and generic. Saddle tree sizing is not standard across the industry. The industry’s focus has shifted to designing saddles that are pleasing to the eye and comfortable for the rider.

How can you tell if a western saddle fits appropriately?
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Place the saddle on the horse with a saddle pad, and check the rock by pressing down alternately on the front and back of the western saddle. If it moves a lot, the stone of the bars is too much. If it moves a little, then check for bridging.

Check for bridging, undo the cinch, lift the fender out of the way and run your hand along the bars between the saddle and the horse in one smooth motion, front to back. Repeat. Pay attention to the saddle’s weight as your hand passes through—less weight in the middle of the saddle and its bridging.

Check that the angle of the front and back of the bar of the western saddle match the horse. Don’t be fooled by the leather angle only.

There should be a flat spot in the seat parallel to the ground, large enough for the width of your sit bones and long enough for your public bone up front. Women typically have a more comprehensive sit bone and a lower public bone up front. You can check your measurement by sitting on a piece of corrugated cardboard on a hard flat surface, squatting down, legs lifted and rolling around to indent those areas. Overlay the cardboard in the seat to see where the pressure point will be for your rear. You can check the center for level by rolling a significant felt marker in the middle after a ride. Women need low or no rise to the front of the saddle seat.

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How tight should a western saddle be?

The cinch should be tight enough to keep the western saddle from slipping sideways but not too close for the horse. A tighter breeze is recommended if your horse does not have a prominent wither.

The flank cinch is required for roping and should be done up snugly, with two fingers fitting between it and the belly. It is dangerous for the horse and the rider if left hanging; your horse could put a foot through.

A flank cinch indicates that the front lock is in the absolute position, meaning it pulls down only on the front end of the saddle and must be used with the rear lock to pull the harness down evenly. 

How far back should a western saddle fit?

The saddle must be placed in the proper location on the horse’s back for the tree’s shape to fit the horse’s body; shift it off an inch, and nothing works as it was designed to. A western saddle tree’s bar tip is designed to fit behind the horse’s scapula while standing straight. The skirting leather will extend past the bar ends in front and back.

Girth Groove

Please don’t place the saddle over the shoulder blade to make the rigging straight, or place it according to concho placement. Find the bar tip in your harness, then find the back of the scapula and put the information behind it. If you have an atrophied pocket behind the scapula, you may need to shim the holes, so the tree doesn’t fall in.

Where should the girth sit on a horse?

You can place it anywhere but always move it to the smallest circumference around the horse’s barrel. The cinch buckle should lay a few inched above the horse’s elbow. Cinches come in a multitude of different shapes, sizes and materials.


Definition of saddle fit

A good saddle that fits your horse for the horse is best defined as maximizing the amount of tree bar contact with the horse while avoiding pressure areas and restricting movement. The tree should distribute the rider’s weight evenly over the horse’s back, lowering the pound-per-square-inch ratio. It should carry the ride comfortably, balanced and securely.

Conditioning and age

Riding a horse without conditioning it for the length of ride you intend to take causes many saddle problems. During the conditioning process, their muscles develop, and their skin toughens in preparation for a long ride. The shape of a horse changes all the time, from unfit and plump in the spring to fully fit after a season of consistent riding. Even after a 20-mile ride, a horse will change.

Age, work, fitness, diet, and muscle change result from work done. A visit from a therapist will also change and relax the muscles. Whether your horse is a novice or experienced, changes will occur. If you go to the gym, you probably do so to get in shape and improve your muscle tone and, thus, your body. Schooling your horse is similar.

Parts of the tree for proper horse fit

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Parts of the tree

The goal of the bars is to distribute the rider’s weight evenly all along the back while providing stability and support to the rider while keeping pressure on the spine and ligaments. To do this, the bars must fit into the area just behind the shoulder blades and should follow the curve and angle of the back, front to back. Check both shoulders since we often encounter horses with asymmetrical shoulders. In that case, you always want to fit the giant shoulder.

Measuring the rock
The Rock

The rock is the curve of your horse’s back from behind the scapula to the end of the western saddle bars, viewed perpendicular to the horse’s back rather than perpendicular to the ground. Locate and mark your horse’s last rib, the base of the horse’s withers, and the back of the scapula to visualize the curve. Then make an offset mark 3.5 inches off the centre of the spine at the last rib and the base of the horse’s withers. Draw a line from the previous rib offset mark up to the back of the scapula, passing through the offset mark at the base of the wither. This is the arc or rocks your tree bars must match for your saddle to fit correctly. Simply changing the gullet width will alter the location of the curve and, most likely, the shape of the rock.

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The Bars

Understanding saddle pad thickness affects fit is essential. A ticker saddle pad will remove rock from the tree. So padding must be considered when fitting a western saddle to the horse.

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Rock in Horse backs
The Angle and Twist

The horse’s back changes angles, beginning steeply in front and gradually flattening toward the rear. This is known as a “twist,” The tree bars must conform to the rock and the twist of the horse’s back for a good fit.

An incorrect angle at any point along the rock will cause the bar’s outer or inner edge to lift off the horse, creating a pressure area and, to some extent, discomfort for your horse. When your saddle is covered in leather, it isn’t easy to see or feel the inner edge.

Bare tree underside view
Gullet area between thee bars
Gullet Width

Gullet width is the term used on the web to solve most saddle fit problems, but that is only one small area of saddle fit to base the whole tree. Changing the gullet width is an excellent way to level the western saddle seat in your harness and prevent you from tilting forward or backward. Getting your saddle to fit correctly with a level seat requires the proper combination of gullet width, rock, and twist all along the horse’s back. Changing one will affect the others. Shopping for or ordering a saddle by gullet width alone is not a good idea.

Measuring for a level western saddle Seat

The western saddle seat must be level for rider security and balance, allowing your bones to work instead of your muscles. Not only is the rider more secure, but it also takes much less effort to ride.

Shoulder Freedom

When the front leg reaches ahead, the scapula rotates back under the front of the bar. This is typically demonstrated by the rider picking up the horse’s front leg and observing the shoulder blade move around and the scapula poke out. When your horse moves its leg, the muscle pulls the scapula back and toward the spine, eliminating the bulge. If you walk beside your horse and observe the shoulder rotation, you will notice that it flattens out and is barely visible. Better yet, saddle up and place your hand under the western saddle to feel the shoulder rotate. The most extensive lump forms when the horse’s leg begins to bear weight. The scapula is still in front of the saddle, and the portion is straight up and down. All the talk about a wider saddle gullet to accommodate scapula movement is false. It usually causes the saddle to tip down in front of the saddle, pinching the area and exacerbating the problem. (Many thanks to Rod and Dennis Nichol.)

Saddle length

A western tree’s bar ends are flared up, and away from the horse’s back so the whole bar does not sit on the horse. The skirting that covers the tree ends should also be flared up and away. The first western saddles were modified versions of Spanish vaqueros’ saddles. They needed a place to transport their bed roll, fencing supplies, and medicine food, so they added saddlebags out behind and the saddle skirting to support them. Vaquero saddles of today have built-in saddle bags on every saddle. Military personnel in English and Western saddles used the area behind the saddle to transport supplies.

Muscle Atrophy

We have observed too much muscle atrophy in the area behind the horses’ withers. The typically wasted muscles are the trapezius, spinal, and or rhomboid, usually due to the narrow tree bars. However, whether too little or too wide, it will prevent all of the back muscles from contracting and extending negatively and adequately impact the psoas, pelvis, and croup muscles. It will affect how the horse uses himself and how willing he is to engage his hindquarters. Muscle damage over time due to an ill-fitted tree can mean permanent damage, and when you see white hairs, the injury is already quite significant.

Measuring with Padding

A lot of advice on the net says to try the saddle fit without a saddle pad. English saddles have padding built into the saddle, while western saddles do not. Understanding how pad thickness affects fit is essential. A ticker pad will remove rocks from the tree. Padding must be considered when measuring and fitting a saddle to the horse. A saddle made to be used with a 1/2 pad will not do better with a 1-inch place.

A pad for your horse must:

  • Be contoured to the horse’s back to prevent bunching under the saddle and to pull the saddle pad tight over the horse’s withers.
  • Allow heat and moisture to escape. Too large a saddle pad with limited air circulation can overheat your horse.
  • Wick moisture away or allow it to evaporate through the material.
  • Be the appropriate thickness for the horse and saddle. Too thin and there may be inappropriate protection; too thick and there could be pinching and compromise the fit.
  • Be the appropriate length and depth for the saddle and horse.

To the rider:

  • Cutouts under the legs and rigging allow for closer contact and keep the pad in place under the saddle.
  • Wear leather to protect the pad from the fender and rider’s leg movement.
Adjustable Saddles

Then, what about interchangeable gullet plates or adjustable systems? They have been one of the best innovations in the world of saddle-making. It sounds so brilliant: just a few screws, and you can adjust your saddle in minutes. Easy! And, of course, you can fit any horse in the barn! This is misleading marketing. It might help a horse pressure its withers from too narrow or too wide a saddle, but it is not the answer to every saddle fit problem.


Remember, though, that most saddle fitting evaluations are unfortunately done in a static state. Therefore, you want to allow some room for the back to move up when the horse is working, depending on its training level and ability to collect.

For your next saddle, ask the saddle maker or fitter what the specs are for this tree, rock, angle, flare, and handhold width. Only through a thorough understanding of the tree’s shape and the shape of your horse’s back in saddle fit can we be more assertive in seeking better-fit solutions and being provided with specific information. We, as consumers, should demand accurate details about the trees that are indeed the foundation of the saddles. Our horses deserve it!

Secondly, please pay attention to the proper fit of the tree itself. Don’t be fooled by fancy gadgets and elaborate options. You can do a lot with shims and pads on adjustable stirrup bars. Still, it will be more fine-tuning, balancing, and compensating for individual conformational or physical issues. Nothing will be able to compensate adequately for a severe mismatch between trees and horses.

So keep this in mind the next time you’re looking for a saddle: proper saddle fitting starts with knowledge of the tree, understanding your horse’s shape, and fitting the tree to the horse.


3D EQUINE SADDLE FITTING SYSTEM eliminates guesswork when measuring your horse and saddle for a perfect fit. Our system measures your horse’s back where the saddle tree bars will lay. Rock, angle, twist, saddle placement area, Gullet width, and wither length. The measurement system also contains templates to measure saddles, go to the tack shop or order a new harness.

You can measure your horse by having one of our saddle reps visits, or you can do it yourself by paying for the kit here. Upon return, we will fully refund the cost of purchasing a saddle or the total price, less shipping and handling, if you decide not to purchase. (If you live outside Canada, ask us how you should mark your paperwork to avoid duty taxes when returning the kit.)

The 3D EQUINE SADDLE FITTING SYSTEM contains everything you will need to complete the task of measuring your horse and saddle. We have an online video you can watch, written instructions you can download, pictures taken at each step of the measuring process, and you can contact us by phone or video app so we can see what you are seeing.