Cotton vs Polyester vs Blends: How to Choose Fabric for Your Clothing

Cotton is a natural plant fibre; polyester is a synthetic fibre made from petroleum-based or recycled plastics. Neither is better overall: they suit different garments.

In short: choose cotton for everyday comfort and print quality, polyester for sport, moisture and durability, and a blend when you want some of both.

• Carded cotton: the standard; fibres are cleaned and aligned, leaving some short, fuzzy fibres.
• Combed cotton: combed further to remove short fibres and impurities, for a smoother, stronger yarn.
• Ring-spun cotton: spun on ring frames that twist the fibres tightly, for a finer, softer and stronger yarn than open-end spinning. Combed and ring-spun together is the premium t-shirt standard.
• Organic cotton: grown without synthetic pesticides or fertilisers. To call a product organic, use certified fabric, such as GOTS-certified.
• Pima and Supima: extra-long-staple cottons with long fibres for softness and strength; Supima is a licensed name for American-grown Pima.

• Elastane (spandex, Lycra) adds stretch. A few percent gives comfort; 15 to 25% gives the compression of leggings and swimwear.
• Recycled polyester is made from plastic bottles or textile waste and performs like virgin polyester. GRS certification backs up a recycled claim.

• Viscose (rayon): made from wood pulp; drapes beautifully and feels cool, but is weaker when wet.
• Modal and lyocell: wood-based fibres that are stronger and softer than standard viscose; TENCEL is a well-known brand of both.
• Linen: from flax; very breathable and strong, and creases easily.
• Wool and merino: warm, breathable and naturally odour-resistant; needs careful washing.

GSM stands for grams per square metre: the weight of one square metre of fabric. It is the standard way to describe how heavy a knit or woven fabric is. The higher the GSM, the thicker, more opaque and usually warmer the fabric.

Weight is not the same as quality. A 180 GSM t-shirt in combed ring-spun cotton can feel better than a 220 GSM one in coarse open-end yarn. Use GSM to set the feel you want, and fibre and yarn to set the quality.

Knit fabrics are made from interlocking loops, so they stretch: jersey, rib, interlock, piqué, French terry and fleece. Woven fabrics interlace yarns at right angles, so they are stable: poplin, twill, denim and canvas.

• French terry: a knit with a smooth face and soft loops on the back; breathable and good for hoodies and joggers all year round.
• Fleece: French terry whose inner loops are brushed into a soft pile; warmer and cosier.
• Jersey: the light, smooth knit of most t-shirts.
• Rib: a stretchy knit with vertical ridges, for cuffs, collars and fitted tanks.

• GOTS (Global Organic Textile Standard): certifies organic fibre and how the textile is processed.
• GRS (Global Recycled Standard): certifies recycled content and its chain of custody.
• OEKO-TEX STANDARD 100: certifies that a textile has been tested for harmful substances.

If you make an organic or recycled claim on a label or website, keep the certificates on file. Advertising rules in most markets require environmental claims to be accurate and backed up.

1. What will the garment be used for: everyday, sport, swim, outdoors?
2. How should it feel: light or heavy, crisp or drapey, stretchy or stable?
3. How will it be decorated? Screen printing and DTG suit cotton; sublimation needs polyester.
4. How will customers wash it? Pre-shrunk fabric or a blend reduces shrinkage.
5. Do you want to make a sustainability claim? Then you need certified fabric.
6. Order a sample in the real fabric and wash it a few times before approving bulk production.