How should I wash my rash guards?

Ultraviolet protection factor (UPF) measures how effectively a rash guard blocks the sun. Many rash guards have UPF coatings that can wash out, so they require gentler treatment than regular clothing. Harsh detergents, hot water, and mechanical stress break down the fabric's UV-blocking properties and stretch-resistant construction.

We'll show you the steps to clean your rash guard so it keeps blocking the sun and fitting right, season after season.

Pre-wash preparation for guard rashes

Before you wash a rash guard, remove sand, salt, or chlorine, as they can accelerate fabric breakdown. These contaminants act like tiny abrasives during the wash cycle and wear away UV treatments.

After you finish your swim session:

• Rinse the rash guard in cool water within 30 minutes
• Turn the garment inside out to protect the exterior
• Gently squeeze out excess water without wringing or twisting

Mineral sunscreens with zinc oxide or titanium dioxide can leave stubborn white stains that regular washing won't remove. To pre-treat these areas, dab dish soap directly on stains and work it in with your fingers before washing.

Body oils and deodorant create yellow stains around collars and underarms. Mix equal parts white vinegar and water, apply to stained areas, and let sit for 10 minutes before washing.

How to machine wash a rash guard to preserve UPF protection

You can wash rash guards in the washing machine if you use the right settings. 

• Water temperature: Cold or cool (60–75°F). Cold water preserves fabric elasticity and UV-blocking treatments that degrade in temperatures above 85°F.
• Cycle selection: Gentle or delicate.
• Spin speed: Low or medium.
• Load size: Small to prevent excessive agitation.

Place your rash guard in a mesh laundry bag to minimize friction against other garments. This prevents snagging on zippers or velcro from other items in the wash.

Wash similar fabrics together. Synthetic rash guard fabrics, like polyester and nylon, have identical care requirements. Don’t wash rash guards with heavy items, like jeans or towels, since they create excessive friction.

Which products should you wash your rash guard with?

Standard laundry detergents contain additives that can damage technical fabrics. Optical brighteners make colors appear brighter but interfere with UV-blocking compounds in UPF swimwear. And fabric softeners leave residue that reduces moisture-wicking properties and traps bacteria.

Choose detergents with these characteristics:

• Free from optical brighteners
• No fabric softener included
• Mild or neutral pH
• Designed for sportswear or delicates

Use half the recommended detergent portion. Rash guards don't get as dirty as everyday clothes, and excess detergent leaves residue that attracts dirt and degrades fabric.

How to dry your rash guard

Dryer heat melts synthetic fibers and degrades elasticity. One high-heat drying cycle can permanently damage a rash guard, so stick with air drying to preserve its UV-protective properties.

• Hang in shade or indoors away from direct sunlight
• Use padded hangers to prevent shoulder stretching
• Reshape the garment while damp to maintain fit
• Provide adequate airflow for complete drying

If you must use a dryer, select the air-dry or no-heat setting. Remove the rash guard while slightly damp and finish air drying. Never use medium or high heat settings.

How to store a rash guard between seasons

Clean and dry the rash guard before storage to prevent mildew and fabric degradation. Store rash guards flat or loosely rolled rather than tightly folded. Sharp creases created by folding weaken the fabric along the fold lines. If you hang your rash guard, use wide, padded hangers that support shoulder seams without stretching.

Choose breathable storage containers. Plastic bins trap moisture that encourages mildew growth. Cotton storage bags or cardboard boxes allow air circulation while protecting from dust and pests.

Keep stored rash guards away from heat sources and direct sunlight. Attics and garages experience temperature extremes that can degrade synthetic fabrics, so choose climate-controlled closets or under-bed storage.

SwimZip: Rash guards that last

SwimZip offers UPF 50+ sun-protective rash guards backed by rigorous testing. Every product carries the Skin Cancer Foundation Seal of Recommendation, so your family can safely enjoy the sun, season after season.

Here’s how we’ve built superior UV protection into our swimwear line:

• Chlorine-resistant fabrics
• Durable construction
• Full-coverage designs

🏊 Explore our sun protective swimwear collection to find sun protection that looks good and doesn’t wash off.

Rash guards FAQ

How often should you wash a rash guard?

Wash your rash guard after every 3–5 uses in chlorinated pools or after each ocean swimming session. Salt water and chlorine require immediate rinsing, but full washing can wait until the garment develops odor or visible soil. Over-washing causes unnecessary wear.

Should I wash a new rash guard before I wear it?

Wash new rash guards before first use to remove manufacturing residues and excess dye. Use cold water and mild detergent on a gentle cycle.

How do I know if it’s time to replace my rash guard?

You should see physical signs of deterioration when your rash guard is worn out. Hold your rash guard up to a bright light. Signs of washing damage to look out for include:

• Permanent stretching that doesn't recover after drying
• Elastic failure at cuffs, waistbands, or necklines
• Color fading from vibrant to pale
• Rough, pilled surface texture
• Seam separation or loose stitching

Small holes compromise sun protection even if they seem insignificant, as UV rays penetrate any opening in the fabric. 

🔎 Learn more about how long it takes for you to burn based on the UV index.

Can you bleach a rash guard?

Never use bleach on rash guards. Chlorine bleach destroys synthetic fibers, removes color, and eliminates UV protection. For brightening dingy white rash guards, soak them in a solution of one cup baking soda per gallon of water for 30 minutes before washing.

Can I dry clean a rash guard?

Dry cleaning chemicals damage synthetic fabrics and degrade UV treatments faster than home washing. The harsh solvents used in professional cleaning dissolve protective coatings and weaken fabric structure.

Professional wet cleaning offers a safer alternative if needed. Some specialty cleaners offer gentle water-based cleaning for technical fabrics. Ask about experience with UPF swimwear before you trust a cleaner with your rash guards.

Further reading

What is the best UV index for tanning?

What are the best rash guards?

Do rash guards keep you warm?

Rash guard vs swim shirt

How tight should a rash guard be?