When the forecast turns bitter and you need a layer that disappears under everything else, the Smartwool Men's Classic Thermal Merino Base Layer Hoodie earns its spot. It is a midweight merino wool base layer with a close-following cut and an integrated hood for extra neck and head coverage. Pull it on and the fabric warms up fast while staying soft enough to keep on from the drive up to the last run.

Why we like it:

The whole thing is knit from 100% merino wool in an interlock structure, so it regulates temperature and fights odor even after several days between washes.

Features and Functions:

Built entirely from 100% merino wool in a midweight interlock knit, this hoodie handles moisture management, thermoregulation, and natural odor resistance the way only merino can. Shoulder panels are engineered to eliminate the top shoulder seams so a pack strap has nothing to rub against, and flatlock seam construction throughout keeps the interior smooth against your skin. The hood sits a little higher on the neck, which adds coverage and warmth when you wear it down.

Fit and Sizing:

Cut slim to sit close to the body, it slides under a shell or midlayer without bunching. If you like a touch more room, size up, but most people find the standard size true.

Bottom Line:

This is the base layer to reach for on genuinely cold days, whether you are skiing lift-served laps or heading into the backcountry. It suits anyone who runs cold and wants merino next to skin without a bulky collar.