Ski boots can make or break a day on the ski hill. After buying all of the gear, waking up early, driving to the mountain, buying lift tickets, and waiting in line to get to the top of your favorite run, there is nothing worse than aching feet telling you to head back into the lodge early. Of course, the best first step towards happy feet is getting a properly fitted pair of ski boots, but an insert can also dramatically affect how your boot feels! Below is a guide to help you buy ski boot insoles.

Boot Fitting 101

Ski boot fitting is a complex process that requires years of experience and dedication. That being said, a few basic measurements go into getting you into the right-fitting boot. Understanding these can help you know what kind of problem your boots may be causing and if inserts will make a difference.

Boot Length

First and foremost, it is crucial to get a boot that fits the overall length of your foot. Unlike street shoes, ski boots are made to fit tight and can be a bit uncomfortable when first trying them on. But rest assured, a tighter-fitting boot almost always equates to more comfort on the ski hill! Less movement within your boot equates to greater ski control, and your foot is less likely to get beat up within the hard plastic shell during a day of skiing.

Boot Width/Volume

Secondly, it is best to get a boot that fits the width of your foot. Ski boots come in different last measurements that equate to different forefoot widths. A larger last (102-104mm) is a great start if you have a wider foot. If you have a narrower foot, narrower lasts (97-99mm) are the best bet. And average width feet should shoot for a boot with a 100mm last. Boots also come in different volumes. Typically, these correlate with the width of your foot, with wider boots having more room for your foot and lower leg and narrower boots having less room overall.

Boot Flex

Lastly, boot flex is an important factor when determining the right boot for you. Not only can the flex change your skiing performance, but it can also affect boot comfort. A boot that is too soft will require you to change your technique to accommodate and result in less foot comfort, typically felt in your ankles. On the other hand, a boot that is too stiff will cause you to ski in the backseat and cause greater pain in your toes and sometimes in your shins. Generally, you cannot change your boot flex with inserts, but a new liner can change the overall ski feel of a boot if needed.

Foot Accommodation 101

Feet have various shapes and sizes, so the three factors mentioned above are usually not enough to get a boot to fit the user comfortably. Starting with a boot that properly fits length, width, and flex is best to ensure that your insoles accommodate your foot, not your boot. If you worked with your Expert to find boots that fit the criteria above, then the following tips are great ways to make adjustments based on your feet.

Arches

Many people have different arch heights. For example, some people have high arches, while others have flat feet. If you have higher arches or suffer from pronation when standing without arch support (that is, your ankles drop inwards towards each other), then buying a ski boot insole with arch support is a great start. Basic footbeds come in standard arch heights, while more advanced footbeds have more customizable heights. In addition, you can use more expensive, fully customized footbeds to match your arches perfectly.

Instep

Another problematic area for lots of skiers is the instep. It’s the area on top of your foot between the ball of your foot and your ankle. If you notice excessive pressure in your instep, this could result from your foot and your boot not having a similarly shaped instep. To solve this, a lower volume footbed with a bit of arch support can bring your foot back in the boot towards the back of the boot. This doesn’t work for all skiers but can greatly alleviate instep discomfort.

For skiers with excessive room in the instep, which one can typically feel by lifting their heel out of the heel pocket, a higher-volume footbed with some arch support can help. Adding the volume-reducing flat shims that come with some ski boots—either in your liner beneath your new footbed or in your boot between your liner and your shell—takes up some of the extra volume within your boot and helps solve instep/heel retention problems.

Ankles

Sometimes ski boots can cause discomfort around your ankles. If it is just the inside of your ankles that hurt, you may be suffering from pronation, and you would benefit from arch support to fix your ankle alignment. If just the outside of your ankles hurt, you could suffer from supination (the opposite of pronation, where your ankles drop outwards), and you likely would also benefit from insoles. Sometimes adding foam J-bars on the outside of your boot liner can also help with ankle pain.

When in the wrong size boot, it is also common to have pressure when your ankle bone doesn’t line up with the ankle area of the boot. Either the void for the ankle is higher than your ankle bone (most common) or lower, and the result is excess pressure on your ankle bone. Adding a footbed with some extra lift can help get your ankle bone into the proper position and reduce pain.

Toes

If your toes cause issues, you can sometimes overcome this with an insert. Many people don’t realize, but adding arch support can shorten the overall length of your foot and pull your toes off the front of your boot. This is a great way to reduce toe pain!

Heels

Occasionally the heel shape of boots is incompatible with the heel cup of the boot. Either the plastic outer shell has a deep heel cup that doesn’t properly lock your heel in place and results in heel lift, or it has a shallower heel cup that pinches your heel and causes pain. Adding an insert can help with heel pain in many ways.

First off, an insert with proper support can help increase heel hold, resulting in a better-fitting boot and better ski performance. Secondly, an insert can raise your heel up and give you a more snug fit at the instep. This allows you to get more ankle hold when tightening the closure buckles of the boot.

Forefoot

Lastly, a footbed can solve problems with the forefoot area and associated pain. Common problems with the forefoot are pain from too tight of a foot, pins and needles feeling from lack of blood flow, or resulting cold feet. Sometimes, a standard footbed can readjust the position of your foot enough to solve this problem, but many times a custom footbed is required.

A custom footbed can be made by a professional by molding the insole to your feet. Although not a purchase that is typically made online, this is a great way to address more tricky boot-fitting problems. Custom insole makers can change the shape of the arch or even add a bump under your forefoot to help increase blood flow to that area. They often finish their work by adding cork to the underside of the insole to help keep the shape of the footbed.

Warmth

Many skiers struggle with cold feet when on the ski hill. Buying heated inserts is a great way to increase comfort while skiing. Heated inserts are basically a footbed with an attached heating device that works like a radiator to heat your feet.

How to Buy Inserts

Inserts are a great start to modifying your boots to get a more comfortable and custom fit. They are easily purchased online and can take care of many problem areas. When experiencing problem areas in ski boots, purchasing an insole can take care of most general issues. If not, moving on to more extensive custom boot fitting, such as custom ski boot liners like Intuition or ZipFit may be necessary. But before pursuing more expensive methods of customization, I highly suggest starting with an insert. If you have more questions about what type of insert to get for your specific needs, reach out to a Ski Expert here on Curated for boot-fitting advice.