Soak swimwear in a vinegar solution.

Soak it in cold water mixed with white vinegar (1 part vinegar to 4 parts water) for 20–30 minutes, then rinse thoroughly. The vinegar neutralizes chlorine and breaks down the chemical residue that causes the smell.

Chlorine bonds to synthetic fibers like spandex and polyester, which is why the smell lingers even after a regular wash. Vinegar cuts through that without damaging the fabric. Baking soda also works, but vinegar is faster and more reliable for heavy chlorine buildup. Hot water sets the smell, so stick with cold.

Your suit will smell like salad dressing for a bit, but that fades faster than pool water.