Beginner surfers and first-time wetsuit-wearers often wonder what they should wear under a wetsuit.
Pants on or pants off? Should you wear a swimsuit? How about your favourite pair of knee-length boardshorts from the early ‘00s? Is it weird to go commando? Even relatively experienced water-goers can find themselves having doubts. The short answer to this surprisingly common question is simple: wear nothing under your wetsuit.
This is the approach adopted by most surfers. But there’s also a longer, more complicated answer. In a number of situations it may be preferable to wear some kind of swimwear or additional layer, such as a rash vest, underneath.

Do you wear anything under a wetsuit?
Most people choose to wear nothing or “go commando” underneath their wetsuit. To some, the idea of a barrier between wetsuit and flesh is as distasteful and absurd as that of underwear to a kilt-wearing Highlands soldier.
Stepping into a wetsuit completely naked, supple rubber sliding over bare skin, is arguably one of surfing’s pleasures. A liberating experience.
Pleasure and pain, however, are never far apart. Skin that is particularly sensitive and/or unaccustomed to long periods encased in neoprene may suffer from rashes or chafing. Vulnerable areas where friction is greatest include around the neck, under the arms, behind the knees, and the all-important inner-thigh interface.
Then there is the question of hygiene, which may be playing on your mind if you’re hiring a wetsuit. (Hire wetsuits should be thoroughly rinsed by the hire place after each use, but we see where you’re coming from.)
Stepping into a wetsuit completely naked is arguably one of surfing’s pleasures
Others may be uncomfortable about getting changed in public. Arriving at the beach wearing swimwear underneath your clothes is one way of anticipating logistical difficulties and preserving your modesty when you come to put your wetsuit on.
(As an aside, another great way to minimise the awkwardness of getting changed is a changing robe or poncho.)
Anyhow, the key thing is to make sure that anything you wear under your suit is close-fitting – no baggy or loose material.
Should you wear a rash vest under a wetsuit?
For the upper body, rash vests (aka rash guards) are the obvious solution to wetsuit rub. Made from a thin lycra fabric, rash vests are most often worn as an outer layer, providing shelter from the sun and guarding the torso area against rashes (from a surfboard or bodyboard, say), but they can also be worn under a wetsuit.
Unlike wetsuits they offer nothing in the way of insulation, so wearing one under your suit isn’t going to make you any warmer. (Thermal rash vests, generally made from neoprene, are an exception to this rule.) It may, however, help protect against chafing or rub thanks to the silkier, less abrasive feel.
Most surfers make do without one, though, perhaps partly because their skin builds up a resistance to neoprene. Alternatively, they may find that the rash vest bunches up a bit and become a nuisance.
If you do plan to wear one under a wetsuit, aim to get a standard close-fitting rash vest and not a “surf t-shirt”. Made from a rash vest material, surf tees are (as the name suggests) a more casual design and fit, so more likely to bunch.
Tips for women
Women are in an advantageous position here, because bikinis and one-piece swimsuits are skin-tight and made of material that won’t bunch up or chafe. They shouldn’t intrude or irritate under your wetsuit, but will stay in place and protect your skin from the rougher texture of a wetsuit.
Many women choose to wear one or both parts of a bikini under their suits, or a classic one-piece swimsuit.
If your skin responds very badly to neoprene, you could even wear a “surfsuit” or body suit – in effect an extended one-piece swimsuit offering additional upper-body coverage and rash protection. Alternatively, pair bikini bottoms with a rash vest, which will also provide coverage round the neck.

Tips for men
The most common faux pas among men is wearing boardshorts under a wetsuit. This is a classic rookie error.
Boardshorts will tend to bunch up under a wetsuit, giving the wearer a wedgie, generally feeling horrible, and if anything increasing the chances of a rash. The same goes for baggy boxer shorts.
Even tight boxer shorts or pants are best avoided. They’re unlikely to be very comfy, they won’t offer much in the way of protection, and you may be left with no dry underwear to change into afterwards.
Boardshorts under a wetsuit will bunch up, give you a wedgie, and generally feel horrible
If you do need some rash protection in that department, wear a pair of speedos or some lycra-style trunks to cover your upper thighs. A rash vest will perform the same function for your top half, including round the neck.
Wetsuit layering: Can you layer wetsuits?
There is one other option we haven’t discussed, and that’s wetsuit layering. Yep, another thing people will sometimes try and wear under a wetsuit is… another wetsuit.
Wearing two 3mm wetsuits at the same time is not the same as wearing one 6mm wetsuit, even if the maths add up
Generally this is done for reasons of warmth. It’s winter, say, and you’ve only got a shorty and a 3/2mm wetsuit, or maybe your winter wetsuit is full of holes, so you wear a shorty underneath.
Now, this is definitely not an ideal solution. Wearing two 3/2s at the same time is not the same as wearing a 6/4, even if the maths add up.
It won’t be very comfortable or very flexible. But it is kind of doable, as a last resort.

As a rule, a much better way to “boost” an old or underpowered wetsuit is to wear a thermal rash vest underneath. Thermal rash vests are generally just half a millimetre or 1mm thick, and are designed to be worn under a wetsuit. They may come with a hood as well, which has the added benefit of giving you a reliable and comfortable seal around the bottom of the hood.