| Material | Polyester knit |
| Job | Breathable mid-layer warmth |
| Strengths | Warm-ish when damp, breathable, cheap |
| Weakness | Not windproof, bulky |
Fleece is a soft, breathable synthetic (polyester) knit used as a warm, quick-drying mid layer. It insulates even when damp, breathes well for active use, and is durable and affordable, though it is bulky and not windproof. Fleece comes in weights from light grid fleece to heavy jackets.
Where it fits
A breathable mid layer for active use; Polartec is the best-known fleece maker. It’s not windproof — a softshell or shell adds protection.
Frequently asked questions
What is fleece?
Fleece is a soft, fuzzy synthetic fabric (usually polyester) used for warm, breathable mid layers. It traps air to insulate, breathes well during activity, dries quickly, and keeps some warmth when damp, making it a versatile and affordable outdoor staple.
Is fleece warm?
Fleece is warm for active use and breathes well, but it's not very warm for its bulk and offers no wind protection — a breeze cuts right through it. For serious cold or stops you'll want a puffy or a shell over it; fleece shines as a breathable mid layer while moving.
Fleece or a puffy for a mid layer?
Fleece breathes better and works well while you're active and sweating, but is bulky and not very warm; a down or synthetic puffy is much warmer and packable for cold and rests but less breathable. Many people carry fleece for moving and a puffy for stopping.
Sources
- Fleece and mid layers — Polartec