Ski boots: if you’ve ever worn a pair you’re probably familiar with the discomfort, blisters, and even numbness that can occur after having your feet in hard, plastic shells for extended periods of time. However, ski boots should never be uncomfortable. Regardless of what you’ve been told or have thought since you first put a pair on, your ski boots should provide all day comfort without experiencing aches, pains, numbness, or tingling. A common overlooked aspect of ski boots is that they come in a variety of widths (known as lasts which we cover below), and volumes. These characteristics are integral to finding a comfortable pair of boots that fit the unique shape of your feet the best. This means it’s ill advised to buy the boot your friend continually raves about and it makes finding a proper fitting pair online nearly impossible without getting a professional boot fit and trying on a variety of boots. 

Get ready to take a deep dive into the world of ski boots and how to find your perfect pair for comfortable skiing all season! 

Buy in Store Instead of Online

It’s well-known you can find steeper discounts online than in a brick and mortar store. And everyone loves saving money, but in this instance, saving money short term can lead to spending more money long term. If the boots you bought online don’t fit well, they will likely require additional modifications to make them fit which you’ll have to pay full price for and spend more time in the shop getting them adjusted. Potentially to an extreme and expensive degree if they are really not meant for your foot shape. If they really don’t fit well, you’ll have to cut your losses, resell them, and start your search all over again. There’s a good chance you won’t notice the boots don’t fit well until you’ve skied them, which makes for a painful day and a hassle to return since they’ve been used. If bindings have already been mounted for ill-fitting boots, it costs money to get skis remounted or adjusted. Lastly, a pair of boots that doesn’t fit has the potential to cause irreparable nerve damage to your feet and which can have lasting effects.

Every year we see countless people come in to get boot work done, complaining of blisters and pain, only to discover their boots are a size too big and/or are not the right profile for their feet. Buying in store provides the added benefit of getting a bootfit by a qualified expert for an hour (for free!) and you’ll likely walk out with a pair of comfortable boots that are ready to be skied without requiring additional work. Mountain Shop understands that a hard plastic shell won’t fit every foot out of the box, so 2 hours of free bootwork is included with each boot purchase. Bootwork is usually $80/hour, and if a lot of modifications need to be done, it can cost upwards of $150. There are variations in size, flex, and materials so it’s always best to talk to an experienced boot fitter first and learn what boots best suit your needs.

Skier Type

Obviously, the most important part of a boot is the fit (if you haven’t already picked up on that), and the best way to determine that is by seeing a bootfitter who knows what boots will fit your feet best. Along with the fit and size, discuss what kind of a skier you are to accurately determine the appropriate boot flex. Boot flex is what it sounds like: it’s the rigidity of the boot’s shell which determines how easy or difficult it is to flex the boot when you press into the front with your shin. In general, a stiffer boot will increase its responsiveness, the efficiency of its rebound, and the energy delivered to the ski . Stiffer boots require more force delivered through the shins, to flex the boot and maintain a proper skiing position. They are typically ideal for Type III aggressive skiers and racers. If one gets a boot that’s too stiff for their ski ability they’ll have a harder time flexing it which will cause their center of mass to be too far back on the ski. This results in an inability to turn and control the ski efficiently; and usually causes sore shins from shin bang. On the other hand, if one gets a boot that has too soft of a flex, it will collapse under the weight and leverage of the skier which puts too much of a bend in the knee. This results in muscle fatigue, instability in turns and at high speeds, and a noticeable drop in performance.

Boot Flex

Most boots have the flex included in their name and usually it’s printed on the shell. The stiffness of a ski boot is characterized by a range of numbers, but it differs between brands so there’s no universal standard for flex. It also differs based on type of boot; a race boot will be stiffer than a recreational boot with the same flex due to the use of higher-end plastics and a difference in plastic thickness. Manufacturers are continuously improving the plastics used in boots so there is some variation from materials used. Something to keep in mind while trying on boots is that the boot at room temperature will have noticeably more flex than on the mountain in below freezing temperatures.

Soft Flex

Women: 50-70 / Men: 60-80 

Medium Flex

Women: 70-90 / Men: 80-100

Stiff Flex

Women: 90-100 / Men: 110-125

Very Stiff Flex

Women: 110+ / Men: 130+


Ski boots don’t adhere to US or European shoe sizes and there’s no difference between men’s and women’s sizing. Ski boots use a measurement called mondo size, which is based on how long the boot is in centimeters. That way, there is some standardization in sizing unlike the flex rating. However, there will be differences between models of boots, as a racing boot in a 27.5 will be shorter than a traditional alpine boot of the same size. This is because race boots have a tighter, performance fit to increase efficiency of power transfer from boots to skis. Normally, skiers who don’t race prefer a slightly larger fit for added comfort and warmth. However, it’s easy to size up too much and wind up in a boot that’s too big, which leads to a loss of power transfer, blisters, and painful shin bang. Again, this is why it’s important to see a professional to find the correct size and fit! It’s also important to factor in the liner thickness when trying on brand new boots: it is the thickest it will ever be and over time the liner will pack out, creating a few extra millimeters of space. 


The last, or width of the boot (and your foot), is an important factor to keep in mind. If boots are too narrow, they will pinch your forefoot causing pain and discomfort along with a decrease in circulation. Boots that are too loose will result in excessive foot movement which leads to a lack of control, stability and ability to get your skis on edge. Last is determined by the width of the foot measured at the 5th metatarsal, or the widest part of the foot. Narrow: 95-98mm last, Average: ~100, and Wide: 102-106. Bootfitters will always check your last before grabbing appropriate boots for you to try on! 


Everyone’s feet are different and the volume of a foot is no exception. A low volume foot takes up less space overall. A high volume foot is the exact opposite, taking up more space. Foot volume often coincides with last but not always.


Boots should be snug when trying them on. When we fit a customer, we tell them to expect their toes to kiss the front of the boots when standing erect. Then when they drop into a skier stance their toes should pull away from the front and no longer touch. Since people are accustomed to how regular shoes should fit, it’s easy to unintentionally size up and get a boot that’s too big. A ski boot should feel like a firm handshake, with no heel lift while walking and no empty space between boot and foot. Think of a ski boot as an extension of your foot, not something to wear over your foot.

Did you know there is a specific order you should be buckling your boots in? Don’t worry, you're not alone.

When putting boots on, it’s important to buckle them in a specific order to ensure the best fit. Here is how you should be buckling your boots:

  1. Start with the second one down, just above the ankle. 

  2. Then do the topmost buckle. You may have to alternate between these two a couple times to get the tightness you desire; do this before moving to the ones on the forefoot. 

  3. Once you have the top two buckles on the desired tightness, buckle the last two starting with the buckle by the ankle and moving towards the toes.

Here’s the why behind this specific buckling order:
Doing the second buckle first ensures the heel gets pushed into the heel pocket putting it in the correct position. If one starts with the forefoot buckles (e.g buckling from bottom to top), the foot gets locked down before the heel is pulled back, causing it to be too far forward which leads to discomfort.

Quick side note about socks: thicker does not mean better and only one pair is needed. Wearing two pairs of socks or socks that are too thick take up too much room in the boot. This reduces the air pocket which helps keep feet warm and restricts blood flow, causing foot numbness. We recommend wearing a thin sock for all day comfort. 

Common Issues and Solutions

Here are some common issues that people run into with their ski boots, and things that can be done to remedy the discomfort.

Boots can be too tight or too loose, but thankfully there are ways to adjust the buckle ladders to either give more space or tighten. In general, the top two buckles have three different holes the ladder can be adjusted to. It’s really quick and easy to take a hex or Philips screwdriver to move them in or out. All the buckles tend to be micro adjustable, simply twist the latch part clockwise to tighten or counterclockwise to loosen if between 2 of the ladder notches. 

If someone has large calves, they can experience pain in the form of pinching on the calf or foot numbness from lack of circulation. As mentioned above, the buckle ladders can be moved out, or the boot can be brought in and have some heel lifts inserted by a bootfitter. The latter will elevate the heel and calf which minimizes how much of the leg is in the boot and cause a noticeable increase in comfort. Women tend to have larger calves than men so many women-specific boots have a lower liner height in the back to compensate for this.

If there’s a lack of arch support or the foot pronates too much in the boot, aftermarket insoles are a great way to provide necessary support and help lock the foot into place in the heel cup while keeping the foot in its natural, active position. If arches are symmetrical and fit drop-in insoles, it’s easy to replace the cheap insole placeholders manufacturers use with proper fitting insoles. We recommend insoles to every customer because the placeholders that come in boots offer no support. Replacing them can immediately increase comfort and performance of the boot. Mountain Shop also offers custom insoles. We take a mold of your feet, heat up our high end insoles, then place them in your foot mold to cool so you have insoles that fit each foot perfectly. Custom insoles not only match the shape of your feet, they also last longer than drop-in insoles and increase comfortability and performance.

Boot Modifications 

Along with the changes mentioned above, bootfitters can do a surprising amount of work on a boot to get it to fit comfortably. If someone has a bunion, 6th toe, or pressure spot, bootfitters can heat and press out the shell to add more room. It’s amazing how a few millimeters of extra space can alleviate pain and pressure! 

Cuff alignment helps if an individual is knock-kneed or bow-legged. It adjusts the angle of the upper cuff to ensure the boot is equidistant from the lower leg all the way around. Most boots have the capability to adjust cuff alignment built right in but it’s always a good idea to have this done professionally. 

Boot Care

Ski boots are an expensive investment that should last for several years before needing to be replaced. There are a couple of really easy tricks to maintain boots that we always recommend doing. First off: after skiing, fully remove the liner from the shell and allow it to air dry or place on a boot dryer. If the liner is left in the shell, even on a boot dryer, the outer part of the liner that touches the shell will never dry. Allowing sweat to build up leads to mold, mildew, really stinky boots, and causes the liner to degrade quicker. Our second recommendation is to ALWAYS buckle boots when not in use. Once they’re fully dried and the liner is reinserted, the boots should be loosely buckled to maintain the cuff shape and prevent the plastic from forgetting its shape. 

Now you're armed with a wealth of knowledge and have a better idea of how boots should fit, feel and function! Stop by to talk to an experienced bootfitter or schedule a bootfitting appointment now!