Cotton and polyester are the two most common fabrics in your wardrobe. One's been worn by humans for 7,000 years. The other was invented in a lab in 1941 and is made from the same material as plastic bottles.
Here's an honest, no-spin comparison of how they actually perform where it matters: on your body.
Comfort
Winner: Cotton, decisively.
Cotton fibres are soft, flexible, and naturally smooth against skin. They bend with your body rather than creating friction. There's a reason babies' clothes are made from cotton — it's the gentlest common fabric against human skin.
Polyester feels slick, slightly plasticky, and doesn't have that natural "give" against skin. It's not painful or intolerable — but side by side, nobody picks polyester for comfort. It creates more friction, generates static, and has a characteristic synthetic feel that most people instinctively dislike.
Breathability & Temperature
Winner: Cotton (overwhelmingly in warm conditions).
The numbers aren't even close:
- Cotton absorbs 8.5% of its weight in moisture. Polyester absorbs 0.4%.
- Cotton has an open fibre structure that allows air circulation. Polyester's is dense and sealed.
- Cotton wicks moisture INTO the fibre (away from your skin). Polyester lets moisture sit on the surface against you.
In practice: wear a cotton t-shirt on a warm day and you'll feel the fabric breathing, pulling light perspiration away from your body. Wear a polyester t-shirt and you'll feel heat building, sweat pooling, and that clammy "greenhouse" sensation within minutes.
Odour
Winner: Cotton, dramatically.
This is polyester's worst category. Studies show odour-causing bacteria (Micrococcus, Staphylococcus) proliferate on polyester at 5x the rate of cotton under identical conditions.
Why? Cotton absorbs sweat into its fibre core, making the surface less hospitable for bacteria. Polyester's hydrophobic surface repels moisture but lets bacteria cling and feed on the oils sitting on the fabric surface.
The practical result: your polyester gym shirt smells rank after one session. A cotton tee worn for the same activity smells noticeably less. And polyester retains odour even after washing — bacteria embed in the fibre surface and aren't fully removed by standard detergent.
Durability
Winner: Polyester (technically).
Polyester is stronger than cotton in tensile tests. It resists stretching, holds its shape better, and doesn't shrink in the wash. It's also more resistant to UV degradation and can withstand more wash cycles before structural breakdown.
BUT: this advantage is theoretical for most clothing. A well-made cotton t-shirt lasts years with normal washing. The durability advantage of polyester matters in industrial applications, outdoor gear, and workwear — not in everyday clothing that you'll cycle out of your wardrobe within 2-3 years anyway.
And polyester has its own "durability" problems: pilling. Those little bobbles that form on the surface after a few washes? That's polyester fibres tangling and matting together. A polyester jumper might be "durable" in that it doesn't fall apart — but it looks terrible after 10 washes because it's covered in pills.
Wrinkling
Winner: Polyester.
This is polyester's genuine advantage. It resists wrinkles. You can pull a polyester shirt from a suitcase and it'll look fine. Cotton wrinkles if you look at it wrong.
If wrinkle-resistance is your top priority (travel, business wear), polyester or blends have a genuine edge. But consider: linen wrinkles even more than cotton, and people pay a premium for it because it looks and feels so good. Wrinkles aren't always a problem — they can signal quality.
Environmental Impact
Winner: Cotton (with caveats).
- Polyester is made from petroleum. Cotton grows from the ground.
- Polyester sheds 900,000 microplastic fibres per wash into waterways. Cotton sheds biodegradable fibres.
- Polyester takes 200+ years to decompose. Cotton decomposes in months.
- Cotton uses more water to grow (though this varies enormously by region and farming practice).
Neither is perfect. But microplastic pollution from synthetic clothing is an escalating crisis, while cotton's environmental issues are largely manageable with better farming practices.
When Polyester Actually Makes Sense
Fairness requires acknowledging where polyester has legitimate advantages:
- Raincoats and outerwear — water resistance is genuinely useful
- Swimwear — needs to be wet constantly without degrading
- High-intensity athletics in cold weather — dries faster than cotton when soaked
- Industrial workwear — where maximum durability matters more than comfort
For everything else — everyday tops, dresses, shirts, trousers, underwear, sleepwear — cotton is the better fabric for human comfort.
The Verdict
Cotton wins for everyday clothing. It breathes better, feels better, smells less, and is better for the environment. Polyester wins for specific technical applications where durability and water resistance matter more than comfort.
The problem isn't that polyester exists — it's that fast fashion brands use it for EVERYTHING because it's cheap, regardless of whether it makes sense for the garment. A cotton dress and a polyester dress serve different purposes. You should get to choose. And to choose, you need to see what things are made of.