I am not prone to superlatives, but here’s one I feel confident dropping: If you ski, three-quarter-length base layer bottoms are an absolute must.
I come by this strong belief not only from my own personal experience as a Mount Ashland season pass holder and avid backcountry skier, but also from talking with many experts and testing base layers for ϳԹ’s Winter Buyer’s Guide. A three-quarter-length layer—one that hits just below the knee and above the calf—is right for all skiers, whether they’re earning every vertical inch skinning up or using the wonderful invention of ski lifts.
Recently, I interviewed ski coach Ryan Pyles and Abigail Dougherty, buying manager at Aspen Ski Company, for a column about proper layering for in-bounds skiing. Both hammered home how important it is to avoid crowding your boots with bunchy socks that overlap with full-length tights. “The rule is ‘socks only’ in ski boots,” says Dougherty. A few months before that, I spoke with pro ski mountaineer Brody Leven to glean his tips for layering. Leven puts so much importance on three-quarter-length base layers that he will trim his wool bottoms with scissors himself if he has to.
Why all the hype? Two reasons. The first is that maintaining blood flow to and from your feet keeps them warmer and prevents them from cramping while you’re skiing. Your ski boot is designed to be tight for precise control and energy transfer to your skis, and any fold of fabric underneath will constrict blood flow and reduce power. This is why boot fitters and pros all suggest wearing the thinnest ski sock you can find. Full-length tights overlapping with those socks only ups your chances of numb toes.
Reason number two: Folds are prime spots for chafing, which leads to blisters and raw skin after even just a few runs.
After two seasons of heavy use, my three-quarter-length base layer bottom of choice is ($85). They’re built from synthetic Polartec Power Grid, which has a waffled network of lofted squares separated by channels of see-through gossamer polyester. The fleecy grid traps heat, while the channels breathe and move sweat away from the skin. The thermal weight is too hot for backcountry spring days but ideal for resort skiing—and the mandatory ass-chilling chair-lift rides.

If you run extremely hot and would be left sweltering in a thermal layer, I suggest the First Lite Glenbrook 3/4-Length Aerowool Bottoms ($90). The Aerowool in the name refers to the fabric—merino bonded with a moisture-wicking and odor-quashing treatment.
Now, I condone a lot of specialized gear purchases. And that’s exactly what this is. So go ahead: Upgrade your full-length skiing long johns. Your chafe-free shins will thank you.