Types of Swimming Fabric: A Guide for Swimwear Brands

The main types of swimming fabric are nylon-spandex (soft, stretchy, best for fashion and resort wear), polyester-spandex (chlorine-resistant, durable, best for active and training use), PBT polyester (virtually chlorine-proof, the gold standard for competitive swimwear), and recycled nylon or rPET (eco-friendly alternatives with comparable performance). The right choice depends on your end use, printing method, and how frequently the suit will see pool or ocean water.

Choosing the wrong fabric is one of the most common and costly mistakes in swimwear production. A suit that looks great in editorial photos but sags, fades, or loses elasticity after ten pool sessions damages your brand. This guide breaks down every major swimwear fabric by technical spec, performance, print compatibility, and use case so you can make the right call before you go to production.

What makes a fabric suitable for swimwear

Not every stretch fabric works in water. Swimwear fabric needs to meet several technical requirements simultaneously: 4-way stretch so the suit moves with the body in all directions, strong elastic recovery so it snaps back without bagging after repeated wear, chlorine and saltwater resistance so the fibers don’t break down, UV protection (UPF rating) for outdoor use, and fast drying so the suit doesn’t stay wet and heavy.

Natural fibers like cotton absorb water, sag when wet, have near-zero chlorine tolerance, and lose their shape quickly in pool environments. That’s why virtually all performance and fashion swimwear uses synthetic fibers, most commonly nylon or polyester blended with spandex (also called elastane or Lycra). The blend ratio and fiber type determine where the fabric sits on the comfort vs durability spectrum.

Types of swimming fabric

Nylon-spandex (polyamide-elastane)

Nylon-spandex, also known in the trade as polyamide-elastane, is the traditional luxury swimwear fabric and the material of choice for high-end resort, editorial, and fashion-forward collections. Nylon has a naturally higher luster than polyester, giving finished garments a subtle sheen that reads as premium even in solid colorways. It is softer against the skin, drapes more fluidly over the body, and accepts dye more evenly, which is why it photographs better and is consistently preferred by brands that sell through editorial and social channels.

• Typical blend: 80% nylon / 20% spandex (common); 75/25 for more stretch, 85/15 for firmer structure
• GSM range: 200 to 250 GSM for outer fabric; 90 to 100 GSM for lining
• Chlorine resistance: Moderate; shows color fading and elasticity loss after roughly 80 to 120 pool sessions
• UV protection: Moderate; can be treated for UPF 50+ but not inherent
• Print compatibility: Excellent for digital and direct printing; rich color absorption and photorealistic patterns
• Best for: Fashion swimwear, bikinis, luxury resort wear, editorial collections, occasional beach and pool use
• Not ideal for: Daily training, competitive lap swimming, heavy chlorine exposure

Polyester-spandex

Polyester-spandex is the industry standard for performance and active swimwear. Polyester fibers resist chlorine degradation far better than nylon, and modern finishing has significantly closed the gap in softness, making it far more comfortable than its reputation suggests. It dries faster than nylon (polyester absorbs less water), holds color better in chlorinated environments, and costs 20 to 30% less per meter, making it the default choice for swim teams, training suits, water parks, and any brand where durability and reorder volume matter more than tactile luxury.

• Typical blend: 85% polyester / 15% spandex (standard); 80/20 for fashion-active crossover
• GSM range: 200 to 280 GSM outer; 100 to 120 GSM lining
• Chlorine resistance: High; maintains color and elasticity significantly longer than nylon under pool conditions
• UV protection: Good inherent UV resistance; achieves UPF 50+ in most constructions
• Print compatibility: Best base for sublimation printing, which bonds permanently with polyester fibers for vibrant, wash-resistant prints
• Best for: Training suits, water park and resort uniforms, outdoor swimwear, brands that print via sublimation
• Not ideal for: Ultra-premium feel or editorial styling where nylon’s sheen is the visual goal

PBT polyester (polybutylene terephthalate)

PBT is a specialized polyester with a molecular structure that inherently repels chlorine rather than just resisting it, making it the gold standard for competitive and high-frequency swimwear. A well-specified PBT blend maintains color vibrancy and structural integrity through 200 or more pool sessions, a benchmark nylon and standard polyester cannot match without significant chemical treatment. PBT also has natural elasticity in its fiber, which means a lower spandex content is needed to achieve the same recovery, producing a fabric that stays compressive and supportive under repeated full-body movement. Because of this, it is the dominant fiber in professional racing and training suits worldwide.

• Typical blend: PBT/polyester 50/50 or PBT-dominant blends; spandex content 15 to 20%
• GSM range: 190 to 220 GSM for competition suits; slightly heavier for training
• Chlorine resistance: Very high to virtually chlorine-proof; suited for daily pool training
• UV protection: Excellent; dense weave and polyester base provide strong UPF ratings
• Print compatibility: Good for sublimation; slightly less vivid than standard polyester in direct comparison
• Best for: Competitive racing suits, swim team uniforms, daily training, aquatic staff uniforms, any suit that needs to survive a full season
• Not ideal for: Fashion-led editorial styling; slightly stiffer hand-feel than nylon

Recycled nylon (rPA) and recycled polyester (rPET)

Recycled nylon (often marketed as ECONYL, made from reclaimed fishing nets and industrial waste) and recycled polyester (rPET, made from post-consumer plastic bottles) perform comparably to their virgin counterparts and are rapidly becoming a non-negotiable for brands with sustainability positioning. Recycled nylon carries the same soft hand-feel, stretch, and print quality as virgin nylon. Recycled polyester (rPET) matches standard polyester for chlorine resistance, UV stability, and sublimation print performance in most independent lab tests. The key sourcing requirement is GRS (Global Recycled Standard) certification from the mill. Without it, any “recycled” or sustainability claim at retail carries both regulatory and reputational risk.

• Typical blend: Same ratios as virgin equivalents (80/20 rPA-spandex; 85/15 rPET-spandex)
• GSM range: Mirrors virgin counterparts
• Chlorine resistance: Comparable to virgin equivalents when GRS-certified
• Cost premium: 10 to 20% higher than virgin versions
• Certification needed: GRS (Global Recycled Standard) from the mill; OEKO-TEX for chemical safety
• Best for: Sustainability-led brands, B-Corp or ESG-focused companies, any brand making recycled content claims at retail
• Not ideal for: Budget-first production where cost per unit is the primary constraint

Xtra Life LYCRA and specialized elastanes

Standard spandex (elastane) degrades in chlorinated water over time, which is why several premium elastane variants have been engineered specifically for swimwear. Xtra Life LYCRA (by Invista) is the most widely known, engineered to resist chlorine breakdown and maintain its stretch and recovery significantly longer than commodity spandex. Creora HighClo is another chlorine-resistant elastane variant used in competitive and training suits. These specialized elastanes are always used as the stretch component in a blend rather than as a standalone fabric, and they command a price premium but meaningfully extend garment life when the base fiber is nylon.

• Role in construction: Stretch component only (15 to 25% of the blend)
• Chlorine resistance improvement: Significantly extends the usable life of nylon-based swimwear
• Best for: Premium nylon swimwear that needs to compete with polyester’s durability
• Key brands: Xtra Life LYCRA (Invista), Creora HighClo

Natural and semi-natural alternatives

Cotton, hemp, and bamboo-based fabrics are sometimes explored for “natural” or sustainability positioning, but all have significant limitations in water. Cotton absorbs water heavily, loses its shape when wet, has almost zero chlorine tolerance, and dries slowly. Hemp and bamboo-based fabrics (usually rayon or lyocell derivatives) are more eco-friendly in production but similarly not suited to repeated pool or ocean exposure. These materials appear occasionally in beach cover-ups, board shorts, and resort-casual pieces where water immersion is minimal, but they are not viable for swimsuits designed for actual swimming.

• Best for: Beach cover-ups, resort casual, board shorts with minimal water contact
• Not suitable for: Swimsuits, training suits, or any garment with regular chlorine or saltwater exposure

Fabric comparison at a glance

How to choose the right swimwear fabric for your brand

Start with end use and exposure. If your customer is in a chlorinated pool daily, PBT or polyester-spandex is the only responsible choice. If they’re a resort guest taking occasional dips, nylon-spandex delivers the premium feel and photographic quality your editorial and social content needs.

Then match fabric to printing method. If your designs rely on all-over print, sublimation is the most durable and color-vivid option, and it requires a polyester base of at least 85%. If you’re printing directly (digital inkjet), nylon absorbs dye more richly and gives you better photorealism on complex patterns. Screen printing and embroidery can work on swimwear for logos and placement graphics but are less suited to full-coverage swimwear prints.

Finally, weigh sustainability and certification. If your brand positions around sustainability, recycled nylon or rPET is a credible choice with comparable performance, but only with GRS certification from the mill. Without it, the claim has no legal or marketing substance and exposes your brand to greenwashing risk.

Produce your swimwear line with MFG Merch

Choosing the right fabric is step one. Getting it cut, sewn, and decorated to spec in a consistent, repeatable production run is where most brands hit problems. MFG Merch’s in-house cut and sew facility in Jacksonville, Florida handles custom swimwear and apparel production with low minimums, so you can test your fabric choice and fit on a small run before scaling.

For brands using polyester-spandex, MFG Merch’s sublimation printing service bonds all-over prints directly to the polyester fibers for a vivid, wash-resistant finish that chlorine and saltwater won’t fade, the right decoration method for the right fabric. For full production from spec to finished garment, custom apparel production covers the complete program.

Send your fabric spec, silhouette, quantity, and branding to the team at mfgmerch.com and get a production quote and timeline back directly from the people making your garments.

Frequently asked questions

What is the most durable swimwear fabric?

PBT polyester is the most durable option, withstanding 200 or more pool sessions without significant color fading or elasticity loss. Polyester-spandex is the strong second choice for active and training use. Nylon-spandex is more comfortable but degrades faster in chlorinated water.

What swimwear fabric is best for sublimation printing?

Polyester-spandex (85/15 or 80/20) is the best base for sublimation. Sublimation inks bond permanently with polyester fibers at high temperature, producing vivid, wash-resistant prints. Nylon does not accept sublimation inks effectively.

What percentage of spandex should swimwear fabric have?

Most swimwear fabrics use 15 to 25% spandex. Higher spandex content (18 to 25%) gives more stretch and body-contouring feel but can lose elasticity faster with heavy chlorine exposure. Lower content (10 to 15%) gives better durability, suited to training and sport suits. You rarely need more than 25%.

Is recycled swimwear fabric as good as virgin fabric?

Yes, when GRS-certified. Recycled nylon (ECONYL) and recycled polyester (rPET) perform comparably to virgin equivalents in chlorine resistance, stretch, and sublimation print quality. The cost premium is typically 10 to 20% higher, and GRS certification from the mill is essential for any sustainability claim at retail.

What GSM should swimwear fabric be?

Outer swimwear fabric should be 200 to 300 GSM for adequate coverage, support, and opacity when wet. Lining fabric (tricot or mesh) runs lighter at 90 to 120 GSM. Competition suits often use 190 to 220 GSM PBT for a tight, compressive fit with minimal drag.

The bottom line

Nylon-spandex is the luxury feel choice for fashion and resort; polyester-spandex is the performance and value choice for active use and sublimation printing; PBT is the professional standard for competitive and daily training; and recycled options match their virgin counterparts when properly certified. Match fabric to end use, decoration method, and sustainability goals before you go to production.

If you’re ready to produce, MFG Merch handles custom swimwear from its Jacksonville, Florida facility with low minimums and factory-direct pricing. Start at mfgmerch.com.