The Baffin Borealis Winter Hiking Boot is a lightweight insulated hiking boot rated to -20 degrees with a removable liner, similar to a plastic mountaineering boot, but much more comfortable for hiking in. It’s also suitable for winter backpacking since you can sleep with the liner to prevent it from freezing at night.
The main thing that sets the Borealis apart from a stiff Pebax (plastic) boot is the translucent exterior TPU shell which is soft, pliable, and comfortable to wear. Fully waterproof, it has a gusseted tongue to prevent water from seeping into the boot. A unique side-locking lace system that snaps shut on the laces to prevent heel lift and heel blisters. It’s a fantastic feature that should be included in other winter and mountaineering boots.
While the Borealis sole is more rigid than many single layer winter boots (like the Salomon Toundra, Columbia Bugaboot , or Keen Summit County III), the Borealis is a non-technical winter boot, too soft for kicking steps in hard snow, and lacking a front or rear welt to attach a mountaineering or ice-climbing caliber crampon. However, it can still be worn with properly sized microspikes, and a walking crampon with universal bindings like the CAMP Stalker, making it suitable for non-technical winter hiking, including all of the above-treeline winter peaks I climb in New Hampshire’s White Mountains.
The outer shell has a reflective liner on the top of the sole but provides very little arch support. While the liner has its own removable padded insoles, I’ve found it necessary to replace it with a Carbon Superfeet insole for extra arch support. Consider sizing up a 1/2 size to accommodate insoles if required. Otherwise, the boots fit to size with a normal hiking sock.
The inner insulated boot molds to your foot with body heat, personalizing the fit. It’s reinforced at the heel and on the bottom, a nice detail, because this is where insulated liners wear out with heavy use.
The liner is secured over the forefoot with an elastic band and locked into the TPU shell with a rear velcro strap to lock it in place. In practice, I’ve found it easier to keep the inner boot in the waterproof shell rather than putting it on outside, and then trying to fit the inner boot into the waterproof shell while wearing it. Of course, the shell can still be removed for drying.
The lugs on the Borealis are fairly modest as winter boots go but sufficient for walking on packed snow. However, when worn, the Borealis Boots are noticeably easier to drive with, even with a standard transmission, than a more rigid and heavier-duty mountaineering boot-style sole. The soles have a slight rocker but are still easy to walk with, in part because the shell isn’t rigid, and because they’re so lightweight.
I’ve been very pleased with the Baffin Borealis Boot and think they’re a real find for winter hiking. They’re quite comfortable and warm, waterproof, and easy to use with traction aids such as snowshoes, microspikes, and crampons with a universal binding. Rated for 20 below zero, the Borealis Boots are also quite lightweight, weighing in at just 3.0 pounds for a US men’s size 11…a full two pounds lighter than the old pair of Scarpa Omega Plastic Mountaineering boots (no longer made), also with a removable liner, that I used to wear.
If you already own single layer winter hiking boots for day hiking, I don’t think you need to upgrade to the Baffin Borealis boots. But if you’re looking for a double-insulated boot so you can backpack in winter and sleep with your liners, I’d give the Borealis Boots serious consideration. If you can get by with a walking crampon, there’s simply no need to cripple yourself with a hard plastic mountaineering boot like a Scarpa Inverno or Koflach Arctis Expe when the Borealis provides the same benefits at a fraction of the weight and a lower price.
Disclosure: Baffin provided the author with a sample pair of boots for this review.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.