Polyester vs Cotton Fabric: The Complete Guide for Sportswear Brands & Importers

Quick answer. Cotton is a natural fibre that absorbs moisture into the fibre itself, which is why it feels soft and breathable but turns heavy and slow-drying once you sweat into it. Polyester is a synthetic fibre (PET) that resists absorption and instead moves sweat along the fibre surface, so it dries in minutes rather than an hour. Cotton's moisture regain is roughly 7-8.5%; polyester's is roughly 0.4%. For sportswear specifically — match jerseys, training kit, base layers — polyester and polyester-heavy blends are the industry default because of that wicking and drying advantage. Cotton remains the better choice for off-field, lifestyle and comfort-first apparel where soft hand-feel matters more than moisture management.

Every sportswear programme we quote in Sialkot starts with the same two questions: what fabric, and what weight. Get the fibre wrong and no amount of good cutting, stitching or printing rescues the garment — a cotton match jersey will still be soaked at half time, and a stiff polyester lifestyle tee will still sit unsold. This guide explains the two fibres properly, at the level a buyer needs to specify a fabric on a tech pack, then covers blends, sustainability, and where these fabrics are actually manufactured in Pakistan and China.

What cotton actually is

Cotton is a natural cellulose fibre grown in the seed pod — the boll — of the cotton plant. Three structural facts explain almost everything a buyer experiences in a finished garment:

• A hollow interior (the lumen). Each fibre is essentially a collapsed tube. That internal void holds both air and water, which is what makes cotton feel breathable and cool, and also what makes it heavy when wet.
• Natural crimp. Cotton fibres twist along their length, so yarns trap air pockets rather than lying flat. Air pockets mean loft, softness and airflow.
• A waxy fibre surface. The natural wax layer is why raw cotton feels smooth rather than scratchy, and why scouring and finishing change hand-feel so dramatically.

Chemically, cotton is alkali-resistant but not acid-resistant, which matters in dyeing and in laundry chemistry. It builds very little static, resists pilling reasonably well, and is biodegradable and renewable. The trade-off is agricultural: conventionally grown cotton is water- and land-intensive, and yield and staple length vary by season and region.

For a brand founder, the practical summary is that cotton is a comfort fibre. It rewards you where the garment is worn casually and punishes you where the garment has to manage sweat.

What polyester actually is

Polyester is a synthetic fibre melt-spun from PET — polyethylene terephthalate — a petroleum-derived polymer. The molecular chain contains no meaningful hydrophilic groups, and that single fact drives its entire behaviour in apparel.

Because the polymer cannot take water vapour into the fibre, moisture has nowhere to go except along the outside of the filament. That surface transport is what the industry calls wicking, and it is mechanically different from cotton's absorption: cotton stores sweat, polyester moves it to a larger surface area where it evaporates. This is why a polyester jersey feels dry again minutes after a sprint while a cotton one stays clammy.

Polyester also brings:

• High tensile strength and low elongation — it holds up to repeated industrial laundering and hard-wearing team use.
• Excellent dimensional stability — it barely shrinks, and it recovers from creasing.
• Easy engineering — filament shape, knit structure and finishes can all be tuned, which is why "performance fabric" is nearly always a polyester construction.

The downsides are real too: it is not readily biodegradable, it is more prone to static and to pilling than cotton, and it sheds microplastic fibre in the wash. Recycled polyester (rPET) reduces new plastic draw but does not change either the shedding or the biodegradability.

Polyester vs cotton — full comparison table

Property	Cotton	Polyester
Fibre origin	Natural (cellulose)	Synthetic (petroleum-based PET)
Moisture regain	~7-8.5%	~0.4%
Moisture behaviour	Absorbs into fibre; feels damp and heavy when wet	Hydrophobic; wicks along fibre surface; dries fast
Typical drying time (200g wet sample)	~60-90 min	~10-15 min
Breathability (plain/still weave)	High — hollow fibre plus air pockets	Lower unless engineered (mesh/open-knit) or blended
Tensile strength (lab range, warp)	~500-600 N/50mm	~900-1,100 N/50mm
Shrinkage, first wash, untreated	2-5%	Under 0.5-1%
Wrinkle recovery	Low (~40 degree recovery angle)	High (~120 degree recovery angle)
Thermal feel	Cooler (k about 0.04 W/m·K)	Slightly warmer (k about 0.05 W/m·K)
Static / pilling	Low static; less pilling	More prone to static and pilling
Biodegradable	Yes	No (rPET reduces new plastic draw, does not fix biodegradability)
Best sportswear use	Off-field and lifestyle wear, cotton-rich casual teamwear	Match jerseys, training kit, base layers, compression

Figures are typical lab and industry ranges, not guarantees — actual performance depends on yarn construction, knit or weave density and finishing.

Breathability and moisture management, explained properly

"Breathable" is the most abused word in fabric sourcing, because it describes two different mechanisms that behave in opposite ways under sweat.

Cotton is breathable in the passive sense. The hollow lumen and the crimp physically hold air, so a plain cotton weave lets a lot of air through — laboratory air permeability for a cotton plain weave commonly tests around 200 L/m²/s, against roughly 100 L/m²/s for a standard polyester knit. Standing still in a warm room, cotton genuinely feels cooler.

Polyester has no internal capacity at all, so it has to be engineered to breathe: modified filament cross-sections, open-knit and mesh constructions, and moisture-wicking finishes that pull sweat outward to a larger evaporative surface. Mesh constructions largely close the air-permeability gap above.

The nuance that matters when you are specifying fabric: a cheap, dense, unfinished polyester can feel stuffier than cotton, and buyers who have only handled that fabric conclude polyester is hot. A properly engineered wicking knit does the opposite — under sustained sweating it stays dry, light and stable while cotton has already absorbed its own weight in water. Judge polyester on the specific construction, never on the fibre name.

Durability, shrinkage and care

This is where the two fibres diverge most sharply in real operations, especially for teamwear that gets laundered constantly.

• 100% cotton, untreated: typically 2-5% shrinkage on the first wash, so patterns must be cut with shrinkage allowance or the fabric pre-shrunk (sanforised). Wrinkle recovery is low, so garments look creased out of a kit bag.
• 100% polyester: typically under 1% shrinkage, high wrinkle recovery, and shape retention through dozens of hot industrial washes. Prints and heat-applied numbers stay aligned because the base cloth is not moving.
• 65/35 poly-cotton: usually lands around 1-2% shrinkage. That is precisely why this ratio became the global default for uniforms and workwear — it was a deliberate engineering compromise, not an accident of history.

If your programme includes replenishment orders, dimensional stability is also a commercial issue: a fabric that shrinks unpredictably means sizes drift between production runs and you inherit fit complaints you did not cause.

Poly-cotton blends explained

Blending is how you buy back some of what each fibre gives up. There is no universally best ratio, only a ratio that matches the garment's job.

Blend	Typical use	What it trades off
100% cotton	Casual tees, off-field and lifestyle wear	Softest and most breathable; slowest drying; most shrinkage
80/20 cotton-poly	Soft casualwear that needs shape retention	Close to 100% cotton feel, less shrinkage
65/35 poly-cotton	Uniforms, workwear, some teamwear	Classic wash-and-wear balance; about 1-2% shrinkage
50/50	Balanced comfort and durability	Middle ground on absorbency and strength
60/40 to 70/30 polyester-heavy	Training tops, some teamwear	Faster drying and more durable; less natural feel
90/10 poly-spandex or 100% technical polyester	Match jerseys, compression, base layers	Maximum wicking and fastest drying; least natural feel

One practical note for founders: blends also change decoration behaviour. Sublimation only bonds properly to polyester, so a cotton-rich blend forces you toward screen printing, transfers or embroidery. Decide fabric and decoration together, not in sequence — sublimation vs screen printing walks through that decision in detail.

Sustainability — the honest picture

Neither fibre is unambiguously the clean option, and buyers are better served by the trade-off than by a slogan.

Polyester is petroleum-derived, does not biodegrade readily, and sheds microplastic fibre during washing. Recycled polyester (rPET) reduces the draw on new plastic but does not eliminate shedding, and blends shed less microplastic per gram per wash than 100% polyester. Its long service life is a genuine sustainability argument: a jersey that survives four seasons of hot washes is not replaced four times.

Cotton is biodegradable and renewable, but conventional cultivation is water- and land-intensive, and pesticide use varies widely by origin. Organic and BCI programmes address these impacts; they do not eliminate them.

One fairness note, because it circulates as fact online: reported skin irritation from polyester apparel is generally attributed to disperse dyes, formaldehyde-releasing wrinkle-resistance finishes, and humidity build-up caused by low moisture regain — not to the PET polymer itself. If skin sensitivity is a stated requirement for your programme, the useful specification is dye class, finish chemistry and an OEKO-TEX style certification, not simply "avoid polyester".

Choosing fabric for sportswear specifically

Here is how these fibres actually get specified in the programmes we produce:

• Match jerseys: typically 100% polyester interlock or pique knit, around 140-160 GSM. Sublimation-ready, dimensionally stable, dries between halves.
• Training tops and bibs: lighter polyester mesh or open-knit, often with a moisture-wicking finish, where airflow matters more than hand-feel.
• Base layers and compression: technical polyester with 8-12% elastane for recovery and hold.
• Shorts: polyester woven or knit shells, sometimes with a brushed inner for comfort.
• Off-field, fan and staff apparel: cotton or cotton-heavy blends, precisely because comfort outranks sweat management there. This is where 100% cotton and 80/20 earn their place in a sportswear range.

Weight is the other half of the specification, and it is where most first-time briefs are vague — see choosing fabric GSM for activewear for the weight bands we quote against. If you are building a full range rather than a single garment, how to start a sportswear brand covers sequencing fabric decisions alongside tech packs, sampling and minimums.

Where these fabrics are manufactured — Pakistan and China

Belta Sports — beltasports.com B2B sportswear manufacturer, Sialkot, Pakistan. 17+ years producing custom cut-and-sew sportswear — jerseys, training kits and uniforms — in cotton, polyester and blended fabrics, serving customers in 45+ countries. Request a quote at beltasports.com to discuss GSM, blend ratio and minimums for a specific programme.

Other fabric and apparel manufacturers

Pakistan:

• Interloop Limited — Faisalabad. Vertically integrated manufacturer of hosiery, denim, knitted apparel and seamless activewear; supplies Nike, Adidas, Puma and H&M.
• Nishat Mills Limited — Lahore. One of Pakistan's largest composite textile groups, producing yarn and fabric from both raw cotton and synthetic fibre, plus denim and home textiles.
• Masood Textile Mills — Faisalabad. Publicly listed (PSX), vertically integrated knitwear and sportswear manufacturer with in-house spinning, knitting and fabric dyeing.

China:

• Shenzhou International Group Holdings — Ningbo. China's largest vertically integrated knitwear and fabric manufacturer; produces both fabric and finished garments for Nike, Uniqlo, Adidas, Puma and Lululemon.
• Esquel Group — Hong Kong. Premium vertically integrated cotton specialist spanning cotton farming through finished garments — a useful counterpart to Shenzhou precisely because it is a cotton rather than a synthetics specialist.

Sialkot's own position in this picture is worth stating plainly: the city is a cut-and-sew and finishing cluster with roughly a century of sports goods history behind it, not a fibre-producing region. Fabric is bought in from Faisalabad, Lahore, Karachi and, for certain technical knits, imported — then engineered, cut, decorated and finished locally. That is exactly why Sialkot factories run low minimums and short sampling cycles: the flexibility sits in the make, not in the mill.

How to specify fabric on your tech pack

A fabric line that a factory can quote without a follow-up email contains five things:

1. Fibre composition — for example "100% polyester" or "65/35 poly-cotton", stated as a percentage, not a brand name.
2. Construction — interlock, single jersey, pique, mesh, woven twill.
3. Weight in GSM — with a tolerance, typically plus or minus 5%.
4. Finish or performance requirement — moisture-wicking, anti-pill, brushed, peached.
5. Colour reference and decoration method — Pantone or lab-dip approval, plus sublimation, screen print or embroidery.

Ask for a costed sample against that specification before the purchase order, and ask for shrinkage and colourfastness results on the actual production fabric rather than a fabric library swatch. Any serious manufacturer will provide both.

Ordering for a team or club specifically? See our guide to custom team jersey MOQ, lead times and costs.