Wool vs cotton
Both are natural fibers. Both have been used for thousands of years. They behave very differently. Wool is warmer, more odor-resistant, and better in wet conditions. Cotton is cooler, easier to care for, and better for warm weather. Which to choose depends entirely on what you need the garment to do.
| Wool | Cotton | |
|---|---|---|
| Warmth | High — insulates well | Low — minimal insulation |
| When wet | Retains warmth | Loses warmth, feels cold |
| Breathability | Good — regulates temperature | Good — absorbs moisture |
| Summer use | Only fine merino | Yes — standard choice |
| Odor resistance | Excellent — can wear many days | Moderate — absorbs and retains odor |
| Care | Hand wash or gentle cold — no dryer | Machine washable, dryer safe |
| Durability | Good with proper care | Very good — hard-wearing |
| Biodegradable | Yes | Yes |
| Microplastics | None | None |
Is wool warmer than cotton?
Yes, significantly. Wool fibers have a natural crimp that creates air pockets between and within fibers, providing insulation. Cotton fibers are smooth and flat — they provide almost no insulation. A wool sweater at 300 grams provides more warmth than a cotton sweatshirt at the same weight. More importantly, wool retains warmth when damp — the fiber can absorb up to 35% of its weight in moisture without feeling wet, and it still insulates. Wet cotton actively draws heat away from the body, which is why wool is preferred for outdoor and cold-weather use.
Is wool or cotton better for summer?
Cotton is better for most people in summer. It absorbs sweat, releases moisture into the air, and feels cool against skin. Linen is even better for hot weather — it is more breathable than cotton. Fine merino wool (17–19 microns) can work in summer because it regulates temperature and resists odor — useful for travel when you cannot wash frequently — but most people find cotton more comfortable in heat. Standard wool is too insulating for warm weather use.
Is wool or cotton better for sweating?
They manage sweat differently. Cotton absorbs sweat readily and feels comfortable initially, but it holds moisture close to the skin and can feel cold and clammy as it dries. Wool absorbs moisture into the fiber itself rather than holding it on the surface, so it feels less damp. Wool also resists odor better than cotton because the fiber's natural structure inhibits the bacterial growth that causes body odor. For athletic use, fine merino wool outperforms cotton in both comfort during exercise and odor resistance after.
Is cotton easier to care for than wool?
Yes. Cotton is machine washable, dryer-safe, and handles high heat without damage. Wool must be washed in cold water on a gentle cycle (or by hand), cannot go in a hot dryer, and should be laid flat to dry to avoid stretching. Some wool is treated to be machine washable (labeled superwash), but even then it requires cold water and gentle handling. If ease of care is a priority, cotton has a clear advantage.
Which is more sustainable — wool or cotton?
Both are natural, renewable, and biodegradable, which puts them both well ahead of polyester. The comparison between them is more nuanced. Conventional cotton is water-intensive and relies heavily on pesticides — it uses roughly 10,000 liters of water per kilogram of fiber. Wool requires no irrigation and no pesticides, but sheep produce methane and overgrazing causes land degradation at scale. Organic cotton significantly reduces the pesticide problem. Responsibly raised wool (certified under the Responsible Wool Standard or ZQ Merino) addresses land and animal welfare. For environmental impact, certified wool and organic cotton are comparable — conventional cotton has a higher chemical footprint than wool.
Can you wear wool and cotton together?
Yes, and this is a practical approach for layering. Cotton makes an excellent base layer in mild to warm conditions. Wool excels as a mid-layer for insulation. Linen works as an outer layer in warm weather. In cold weather: a cotton or merino base layer, a wool mid-layer, and a wool or wax-cotton outer layer covers a wide temperature range. The layering system works because each fiber does what it does best.