Cotton is the most popular natural fibre on the planet. It makes up roughly 24% of all fibre produced globally, and it's been used for clothing for over 7,000 years. If you own a t-shirt, a pair of jeans, or bed sheets — you already know cotton.
But not all cotton is the same. Here's everything you need to know.
Cotton by the Numbers
- Global production: ~25 million tonnes per year
- Share of world fibre market: ~24% (down from 68% in 1960 — polyester took over)
- Moisture absorption: Up to 27x its weight in water
- Breathability: Excellent — air passes freely through the natural fibre structure
- Biodegradability: 1-5 months (polyester: 20-200+ years)
- Hypoallergenic: Yes — one of the safest fabrics for sensitive skin
Why Cotton Feels Good
Cotton's comfort comes from its natural structure. Each cotton fibre is a single plant cell — a hollow, twisted ribbon that does three things exceptionally well:
- Absorbs moisture. Cotton pulls sweat away from your skin and absorbs it into the fibre. This is why a cotton t-shirt feels comfortable on a hot day — it wicks moisture instead of trapping it on your skin the way polyester does.
- Breathes. The natural gaps between cotton fibres allow air to circulate. Your body can regulate its temperature naturally.
- Softens over time. Cotton fibres relax with each wash. A well-worn cotton shirt gets softer and more comfortable — the opposite of synthetic fabrics that pill and degrade.
Types of Cotton
Cotton isn't one thing. The type of cotton plant, where it's grown, and how the fibre is processed all affect the final fabric.
By Staple Length
Staple length is the single biggest factor in cotton quality. Longer fibres = smoother, stronger, softer fabric.
| Type | Staple Length | Quality | Used In |
|---|---|---|---|
| Short-staple | Under 25mm | Rougher, pills easily, less durable | Budget clothing, fast fashion basics |
| Medium-staple | 25-30mm | Standard quality, good all-rounder | Most everyday clothing |
| Long-staple | 30-37mm | Smooth, strong, soft | Premium clothing, good sheets |
| Extra-long staple (ELS) | 37mm+ | Exceptional softness, durability, lustre | Luxury clothing, high-end sheets |
Premium Cotton Varieties
Egyptian Cotton. Grown in the Nile River Valley, Egyptian cotton is an extra-long staple variety prized for its softness and durability. The warm climate and rich soil produce exceptionally fine, strong fibres. However, the label is widely counterfeited — a 2019 investigation found up to 90% of products labelled "Egyptian cotton" contained none. Look for the Cotton Egypt Association seal.
Pima Cotton. Named after the Pima Native Americans who first cultivated it, Pima is an ELS cotton grown primarily in the southwestern United States, Peru, and Australia. It's 35% stronger and 45% softer than standard cotton. All Supima cotton is Pima, but not all Pima is Supima.
Supima Cotton. A trademarked brand of American-grown Pima cotton. Only cotton grown by licensed US farmers can carry the Supima label, making it one of the most traceable cotton certifications. Represents less than 1% of global cotton production.
Sea Island Cotton. The rarest commercial cotton in the world, grown exclusively in the Caribbean. Extra-long staple with a silk-like lustre. Extremely expensive and genuinely limited in supply.
Organic Cotton
Organic cotton is grown without synthetic pesticides, chemical fertilisers, or genetically modified seeds. The key differences:
- 91% less water from blue water sources (irrigation) compared to conventional cotton
- 46% fewer carbon emissions during production
- No synthetic pesticides — conventional cotton uses 16% of the world's insecticides
- Fewer chemical residues in the finished fabric — better for sensitive skin
- GOTS certification (Global Organic Textile Standard) is the gold standard — covers the entire supply chain from farm to finished product
The fabric itself feels very similar to conventional cotton. The benefits are primarily environmental and health-related (fewer chemical residues against your skin).
Cotton vs Polyester: The Core Difference
Cotton is a plant. Polyester is plastic made from petroleum. That's the fundamental divide, and it affects everything:
| Property | Cotton | Polyester |
|---|---|---|
| Source | Cotton plant | Petroleum (oil refinery) |
| Breathability | Excellent | Poor |
| Moisture absorption | Absorbs up to 27x its weight | Absorbs almost nothing (0.4%) |
| Odour | Minimal — doesn't trap bacteria | Retains odour — bacteria thrive on it |
| Skin safety | Hypoallergenic, dermatologist-recommended | Can cause irritation, rashes, acne |
| Microplastics | None | Sheds microplastics every wash |
| Biodegrades in | 1-5 months | 20-200+ years |
| Cost | Higher (natural, slower to produce) | Lower (petroleum is cheap to process) |
| Wrinkles | More prone | Wrinkle-resistant |
Polyester's only practical advantages are price and wrinkle resistance. Cotton wins on comfort, breathability, skin health, odour, and environmental impact.
How to Spot Cotton Quality
Not all "100% cotton" is created equal. Here's how to assess cotton quality before buying:
- Fabric weight (GSM). Under 140 GSM feels thin and transparent. 160-200 GSM is the sweet spot for t-shirts. Over 200 GSM is heavyweight — more durable, more structured.
- Weave type. Percale (crisp), sateen (silky), and twill (denim) each feel different. Jersey knit (t-shirt fabric) varies enormously by quality.
- Single-ply vs two-ply. Two-ply yarns are smoother and stronger but cost more.
- Check for blends. "Cotton-rich" or "cotton blend" often means 40-60% polyester. Read the full composition label. If it says anything other than 100% cotton, polyester is probably in the mix.
How to Care for Cotton
- Wash in cold or warm water — hot water causes more shrinkage and fading
- Tumble dry on low or air dry — high heat shrinks cotton significantly
- Expect 3-5% shrinkage on the first wash — many premium brands pre-shrink
- Iron while slightly damp for best results — or use a steamer
- Separate colours — cotton dyes can bleed, especially in early washes
The Cotton Problem: Why It's Losing to Polyester
In 1960, cotton represented 68% of global fibre production. Today it's about 24%. Polyester has taken over — not because it's better, but because it's cheaper.
- Polyester costs roughly half as much as cotton to produce
- Cotton requires land, water, time, and weather — polyester just needs an oil refinery
- Fast fashion brands maximise profit by substituting polyester wherever consumers won't notice
The result: even brands that appear to sell "cotton basics" often use cotton-polyester blends. The only way to know for sure is to check the fabric composition label on every product — or use a tool that does it for you.
When to Choose Cotton
- Everyday basics — t-shirts, underwear, socks, loungewear
- Hot weather — cotton's breathability makes it ideal for summer
- Sensitive skin — dermatologist-recommended for eczema, allergies, and irritation
- Baby and children's clothing — safest natural fibre for delicate skin
- Bedding — cotton sheets are breathable, absorbent, and soften with every wash
- Denim — jeans are almost always cotton, and it's the best material for the job
When Cotton Isn't the Best Choice
- High-intensity exercise — cotton absorbs sweat and gets heavy. Merino wool or TENCEL perform better for intense workouts.
- Outerwear in rain — cotton absorbs water and dries slowly. Waxed cotton or wool is better for wet conditions.
- Maximum wrinkle-resistance — if you absolutely can't have wrinkles, linen-cotton or cotton-elastane blends are better choices than adding polyester.