Surfing needs board shorts; lounging needs everything else.

Yes. You need two different pairs if you’re actually going to surf. A single pair that tries to do both will annoy you.

For surfing, the non-negotiables: a tie waist (not elastic), no mesh lining (chafing nightmare), and a length that goes at least to mid-thigh. Boards shorts are longer, tighter, and have a flat front with a drawstring so they don’t come off when a wave hits. Velcro fly or lace-up closure is ideal. They’re basically performance swimwear that says “I might get worked in the shorebreak.”

For lounging, any swim trunk works. Mesh inside, elastic waist, shorter inseam, brighter colors. You’re not worried about them falling down or trapping sand. Brands like Patagonia, Rip Curl, and Billabong make actual board shorts that look good on the beach too. But if you only buy one pair and try to surf in casual trunks with an elastic waist, you’ll be pulling them up all session.

Just get both. One for work, one for play.