Kids Swimwear Buying Guide: Fit, Fabric and Sun Safety

Quick answer

Buy a kids swimwear set that fits snugly now, not one to grow into. Choose chlorine-resistant fabric with a high UPF rating if your child swims often, and always size up only if the suit still passes the stretch and gap test. For sun safety, look for long sleeves or a rash vest, and remember that a wet suit loses some protection—reapply sunscreen.

Start with fit: the two-finger test and the squat check

A swimsuit should feel like a second skin—snug but not restrictive. Put the suit on and check these three spots: shoulder straps (should not slip off), leg openings (should not gape), and torso (should not ride up when arms lift). If you can pinch more than two fingers of fabric at the side seam, the suit is too loose and will balloon in water.

For growing kids, avoid buying a size up 'to last.' A loose suit chafes, drags, and can expose skin to sun. Instead, buy the size that fits now and hand it down when outgrown. If your child is between sizes, go with the larger size only if the smaller one leaves red marks or restricts movement.

• Two-finger test: no more than two fingers of extra fabric at the side seam.
• Squat check: child should be able to squat without the suit pulling down at the back.
• Arm raise: straps should stay in place and the torso should not ride up.

Fabric matters: chlorine resistance, dry time and stretch

Most kids' swimwear uses either polyester blends (often with PBT or elastane) or nylon/elastane. Polyester blends resist chlorine and fading better, making them ideal for frequent pool swimmers. Nylon blends feel softer and stretch more, but they degrade faster in chlorinated water. If your child swims twice a week or more, prioritize chlorine-resistant kids swimwear.

Check the label for 'chlorine resistant' or 'UPF 50+'. UPF indicates how much UV radiation passes through the fabric—UPF 50+ blocks about 98%. However, a wet, stretched suit can lose some protection, so combine with sunscreen on exposed areas. Quick-dry fabrics are a bonus for holidays and back-to-back swims.

• Polyester blend: best for frequent pool use and chlorine resistance.
• Nylon blend: softer feel, better for occasional swims or beach days.
• UPF 50+ rating: blocks about 98% of UV radiation when dry.
• Quick-dry: reduces chafing and is easier to pack for travel.

Sun safety: coverage, style and reapplication

For maximum sun protection, choose a set with long sleeves and high necklines, or pair a rash vest with swim bottoms. Two-piece sets with a tankini top offer more coverage than a bikini and are easier for toilet breaks. For babies and toddlers, look for full-body sun suits with UPF 50+.

Remember that no swimwear replaces sunscreen. Apply broad-spectrum SPF 30+ to exposed areas 15 minutes before sun exposure, and reapply every two hours or after swimming. A wet suit can cling and stretch, reducing UPF effectiveness, so be generous with cream on shoulders, ears, and the back of the neck.

• Rash vest + bottoms: good coverage for active kids.
• Long-sleeve sun suit: best for all-day beach or pool sessions.
• Tankini: more coverage than a bikini, easier for toilet breaks.
• Reapply sunscreen every two hours, even with UPF clothing.

Care tips to make swimwear last

Rinse swimwear in cool fresh water immediately after every swim to remove chlorine, salt, and sunscreen. Hand wash with a mild detergent or swimwear-specific wash—never use bleach or fabric softener, which break down elastane. Lay flat to dry in the shade; hanging by the straps can stretch them, and direct sunlight can fade colours.

Rotate between two suits if your child swims daily. This gives each suit time to recover its shape and reduces wear. Avoid wringing or twisting the fabric, which can cause stretching and pilling. With proper care, a good-quality suit can last a full season or more.

• Rinse immediately after every swim in cool water.
• Hand wash with mild detergent; no bleach or fabric softener.
• Lay flat to dry in shade; avoid direct sun and hanging by straps.
• Rotate two suits for daily swimmers to extend life.

Decision rules for buying kids swimwear

• If your child swims in a chlorinated pool more than once a week: Choose a polyester-blend suit labeled chlorine resistant. It will resist fading and stretching better than nylon. Look for 'chlorine resistant' on the label.
• If you need maximum sun protection for a fair-skinned child: Pick a long-sleeve rash vest or full-body sun suit with UPF 50+. Pair with a swim hat and sunscreen. UPF 50+ blocks about 98% of UV rays when dry.
• If your child is between sizes: Buy the smaller size if it passes the two-finger test and allows full movement. Only size up if the smaller size restricts movement or leaves red marks. A snug fit is safer and more comfortable in water.
• If you want a suit that lasts multiple seasons: Rinse after every swim, hand wash, and rotate between two suits. Avoid hot dryers and harsh chemicals. Proper care doubles the life of swimwear.

Product facts

• Field Of Dreams Silver Organic Cotton Pillowcases: Certified organic cotton printed pillowcases in a hand-painted floral print on a silver grey base. If your child has sensitive skin or you prefer organic cotton for bedding, these pillowcases offer a breathable, gentle option that coordinates with colourful bedroom decor.
• Sunny Granita Sherpa Adult Slippers: Sherpa-lined slippers with a rubber sole and slide shape, packaged for easy gifting. After swimming, these cosy slippers keep feet warm and protected—ideal for poolside or home use, and the rubber sole adds grip on wet surfaces.

Who this guide is for

Best for

• Parents buying a first or replacement swimsuit for a child aged 2–12
• Families who swim regularly in pools or at the beach
• Caregivers looking for sun-safe swimwear options

Not for

• Competitive swimmers needing technical racing suits
• Adults seeking swimwear for themselves
• Those looking for fashion-only swimwear with no performance requirements