Merino Wool Base Layer Tops

How to choose

REI recommends a comfortably close fit for a moisture-managing base layer. That does not mean buying a constricting size. Check that the shirt follows your body without pulling across the back, digging at the neck or limiting your reach.

Choose the neckline around your outer layers. A crew keeps the front simple. A partial zip gives an opening you can adjust, but check how its collar and zipper sit underneath the next garment. Multiple high collars can create a combination you dislike even when each item fits on its own.

Compare sleeve and body length during movement. Reach upward and forward with the outer layer on, then check whether the cuffs and hem stay where you need them. For ski trips, the base-layer selection guide adds the details that matter with that particular clothing system. For casual wear, consider whether a roomier tee would better match the job.