Most people wear something under their wetsuit to help with getting their wetsuit on and off easier. The other reason for wearing something under your wetsuits is that the extra layers can help keep your body warmer. Instead of wearing a thicker wetsuit that will restrict your movement, it allows you to wear a thinner suit that will give you more flexibility. You can wear a short sleeve top or bottom to help keep your core warmer. The other thing to think about is the air temperature/ wind on your way to the dive site. Suppose you are worried about the air temp/ wind when you are traveling to the dive site. In that case, you can wear heavyweight GoreTex or a linebacker jacket (the kind made for helo’s flights/ football players wear on the sidelines) is excellent to have as you can take it off before the dive and put it on when you are done.

SCUBAPRO 1.5mm Everflex SS top

For colder temperatures, adding layers underneath the suit is the way to go. You have several options to choose from. If you already have a thinner wetsuit that you usually use for warmer environments, a 1mm rash guard, or any other type of garment that’ll provide you with the added warmth around your chest will help. SCUBAPRO makes a great 1.5mm top and bottoms in short and long sleeves, shorts, and long pants. This 1.5mm is very warm, and to me, it feels like I am wearing a 2-3mm.

SCUBAPRO 1.5mm Everflex long pants

When you have to worry about the wind, most surf wetsuits or wetsuits glossy like surf suits are made to stop the wind. That all-suit surf suits are not great for diving as most are not made from a material (yes, surfing is different than diving) that is designed to be used underwater for long periods. Some people like to wear nothing between them and their wetsuits. This can be painful after wearing a wetsuit for a long time, especially on a long wet Zodiac ride. Due to the constant rubbing against their skin, it begins to chafe ( AKA Baboon a$$). Usually, the neck, armpits, behind the knees, and the crotch are the first to go. You can apply anti-chafing gel/ Vaseline to help with this on long dives and rides. There is also stuff like Butt Paste, Triple paste, or Anti monkey butt paste.

SCUBAPRO 1.5mm Everflex LS top

You can also wear dive skin or bike shorts; this will help with donning and doffing your suit on and off also. I have started to use Under Armor UA RUSH™ compression shorts. (They make tops also) They are made with a material called Celliant; it is a mineral-infused fabric to take the energy you give off when you work and reflect it into your muscles, increasing blood flow and helping them work harder. As your body emits energy, the mineral-infused fabric absorbs & reflects it, improving endurance. (I know this sounds crazy, but I am a big believer in Celliant)

Whatever you decide to wear, keep in mind the water/ air temperature, duration of the dive, and what you will be doing. Also, one reason you should make sure to keep a logbook of all your dives. That way, you can look up what you have used in the past for this situation. That should put you at a good starting point. Now that you’re aware of your options, it’s time to get to specifics. What type of undergarment is right for your needs, or do you even need to wear anything under your wetsuit at all?

SCUBAPRO 1.5mm Everflex

Well, that depends on you. In warmer waters, you can get away with wearing undergarments with minimal coverage (swimsuits, trunks, and other similar items)—or even nothing at all. Many people prefer to go commando under their wetsuits, but it’s all a matter of preference. If you plan to rent the suit, however, you’re probably going to want to wear something underneath.

SCUBAPRO 1mm Topical wetsuit

For colder temperatures, adding layers underneath the suit is the way to go. You have several options to choose from. Suppose you already have a thinner wetsuit that you usually use for warmer environments. In that case, you can opt to add a jumpsuit, rash guard, or any other type of garment that’ll provide you with the added insulation you need. This way, you won’t have to purchase another suit.

SCUBAPRO Hybrid Hood Vest

Or, if you’d instead go naked warrior underneath, you can get a thicker wetsuit. Deciding what to wear ultimately depends on the environment (and temperature) you plan to dive in, how sensitive your body is too cold, and many other variables. Make sure to consider all factors before you buy anything, and always try it in training before you use it for the first time when it matters the most.