What should I wear under a wetsuit?

Most divers wear very little under a wetsuit because the suit itself is designed to trap a thin layer of water that your body warms. A swimsuit, rash guard, or thin dive skin is usually enough. These layers make it easier to slide into the wetsuit, prevent chafing, and add comfort between your skin and the neoprene.

By Tyler AllisonUpdated December 6, 2025

I personally wear skin-tight rash guard–style biker shorts and a short-sleeve top on every wetsuit dive. It adds almost no warmth but makes getting into the suit easier and provides a bit of modesty when gearing up or getting out of the wetsuit around other divers. Avoid cotton or loose clothing, as it holds water and will make you cold.

What matters far more than what you wear under the suit is how the wetsuit fits. Not all brands fit the same, and some offer extended or in-between sizes beyond the standard small, medium, and large. If your body proportions don’t match standard measurements, many manufacturers offer custom-fit wetsuits for an additional cost. Through trial and error, I found that the Bare XLT cut fits me perfectly. When a wetsuit fits right, it seals properly, keeps you warmer, and makes the dive much more comfortable.