How to Wash Rash Guards So They Last More Than One Season

By Asana Hawaii | Check out our exclusive deals on Island | Published: 2026-10-14

Category: Tips & Care

Learn how to wash a rash guard properly with our step-by-step guide. Keep colors bright, prevent chlorine damage, and extend the life of your swim shirt.

Quick answer

Rinse your rash guard in cool water immediately after every swim, then wash it on a gentle cycle with mild detergent and air dry it away from direct sun. This simple routine removes chlorine, salt, and sunscreen before they break down the stretch fibers and fade the print, so the fit and color hold up for seasons.

Why rash guards wear out faster than you think

Chlorine, saltwater, and sunscreen residue are the main enemies of stretch fabrics. Chlorine oxidizes spandex over time, causing it to lose elasticity and turn brittle. Salt crystals can abrade fibers, and sunscreen oils can attract dirt and weaken the fabric. Even a single afternoon in a chlorinated pool leaves residue that continues to work on the fibers until it's rinsed away. That's why immediate rinsing matters more than the washing machine you use.

What you need before you start

Gather a mild liquid detergent (free of bleach, fabric softener, and enzymes), a clean sink or a mesh laundry bag if you're using a machine, and a towel for blotting. Avoid Woolite or any detergent that contains softeners, as they coat the fibers and reduce stretch recovery. If your rash guard has a UPF rating like the Asana Hawaii Girls Rash Guard, which offers 38-40 UPF protection, harsh detergents can break down the tight weave that provides that sun protection. Always check the care tag first; if it says hand wash only, follow that.

Step-by-step washing routine

Following a consistent routine is the best way to prevent premature wear. Each step below includes a common mistake to avoid so you don't accidentally shorten the life of your rash guard.

Your rash guard care steps

Rinse immediately after swimming: As soon as you leave the water, rinse your rash guard in cool tap water. This removes chlorine, salt, and sunscreen before they set into the fibers. If you can't rinse right away, at least soak it in a sink or bucket for a few minutes before it dries. Checkpoint: the water should run clear, not slippery or foamy.
Pre-treat stains and odors: For stubborn stains or lingering odors, apply a small amount of mild detergent directly to the area and gently rub with your fingers. Let it sit for 5-10 minutes. Never use bleach or harsh stain removers, as they damage spandex and fade colors. Mistake to avoid: scrubbing with a brush, which can pill the fabric.
Wash gently by hand or machine: Hand wash in cool water with a capful of mild detergent, gently squeezing the suds through the fabric. If using a machine, place the rash guard in a mesh bag, select a delicate cycle with cold water, and use a low spin speed. Avoid washing with heavy items like jeans or towels. Checkpoint: the wash cycle should be short and gentle, no more than 30 minutes.
Rinse thoroughly: Rinse in cool water until no soap remains. Detergent residue can attract dirt and irritate skin. If you used a machine, run an extra rinse cycle to be sure. Mistake to avoid: leaving soap in the fabric, which can cause stiffening.
Dry flat or hang in shade: Gently squeeze out excess water without wringing. Lay the rash guard flat on a clean towel or hang it on a padded hanger away from direct sunlight. Direct sun can fade colors and degrade spandex. Never put a rash guard in the dryer; heat breaks down elasticity. Checkpoint: the rash guard should be dry within a few hours; if it stays damp, it may develop mildew.

Product facts that matter for care

Asana Hawaii Girls Rash Guard: 82% polyester, 18% spandex; 38-40 UPF sun protection; very soft four-way stretch fabric that stretches and recovers. The spandex content means heat and harsh chemicals will degrade stretch; gentle washing and air drying preserve the fit and UPF protection.
Kailua Bay Crossover Pocket leggings: Crossover waistband design with pockets; made from soft and stretchy fabric. The waistband and pockets can snag or lose shape if washed with rough items; use a mesh bag or hand wash to protect these features.