Quick answer
To care for a fleece, wash it inside out on a cool or warm gentle cycle (30C is ideal) with a technical cleaner or a mild non-bio detergent, and never use fabric softener, which coats the fibres and kills the warmth and breathability that make a fleece work. Skip the high heat: air dry it or tumble dry on low only, because a hot dryer melts and mats the pile and can distort the garment. Fleece is polyester, so it rarely shrinks from water alone, but excess heat is what damages it. Deal with pilling (the little bobbles that build up with wear) using a fabric shaver or comb, and wash inside out to slow it down. Wash a fleece only when it needs it rather than after every walk, and store it clean, dry and loosely folded or hung.
A fleece is the most forgiving layer in your kit, which is exactly why it gets abused. It goes in the machine with everything else, on whatever wash was already set, and after a couple of years it comes out flat, bobbled and nowhere near as warm as it was. Almost all of that is avoidable.
The good news is that fleece care is simple. Get three things right, the wash, the drying and the pilling, and a decent hiking fleece will stay warm and presentable for years. This guide covers all three, quickly.
How to wash a fleece
Fleece is a synthetic (almost always polyester), so it is easy to wash and quick to dry. The two things that damage it are heat and the wrong products, not the water itself.
The routine that keeps it performing:
- Turn it inside out. This protects the outer face, which is where friction and abrasion do the most cosmetic damage, and it slows down pilling on the side people see.
- Fasten the zips. Open zips snag other garments and stretch the fleece in the wash.
- Wash cool. A cool or warm gentle cycle, around 30C, is plenty to clean a fleece. There is no need for a hot wash, and hot water offers nothing but risk.
- Use a mild detergent, or a technical cleaner. A small dose of mild non-bio detergent does the job. A technical cleaner such as Nikwax Tech Wash goes further: it lifts grime without leaving the water-attracting residue that ordinary detergents leave behind, so the fleece keeps its light water-repellency and dries fast.
- Never use fabric softener. More on why below, but it is the single most damaging thing you can do to a fleece.
If you want one product that does the wash and keeps your waterproofs going too, the Nikwax twin pack pairs the cleaner with a proofer in one box.
Get the Nikwax Tech Wash twin pack on AmazonWhy fabric softener ruins a fleece
Fabric softener feels like it should be kind to a soft garment. It is the opposite.
Softener works by leaving a thin waxy coating on the fibres. On a fleece that coating clogs the tiny air pockets between the fibres, and those air pockets are the entire point of a fleece: they trap warm air against you. Coat them and you lose insulation and breathability at the same time. Nikwax makes the same point about technical fabrics generally, that softener clogs the pores and reduces performance.
It also flattens the loft, leaving the pile matted and lifeless, and can trap odours rather than release them. There is no version of fabric softener that helps a fleece. Leave it out of every wash.
Can you tumble dry a fleece?
You can, but on low heat only, and air drying is safer.
Fleece dries very quickly on its own, so there is rarely any need to tumble it. Hang it up and it will usually be dry in a few hours. If you do use the dryer, keep it on a low or cool setting and check the care label first.
The thing to avoid is high heat. Fleece is polyester, and a hot dryer can melt and mat the pile, flatten the loft permanently, and distort or shrink the garment out of shape. Once the pile has matted from heat there is no bringing it back. Low and slow, or a hanger and a bit of patience, every time.
Dealing with pilling and bobbling
Pilling is the little balls of fibre, the bobbles, that build up on a fleece with use. It is the most common complaint about older fleeces, and it is largely cosmetic rather than a fault.
Why it happens. Friction pulls short fibres loose from the surface, and those loose fibres tangle into balls that stay attached to the fabric. The high-rub zones go first: where a rucksack strap sits, under the arms, around the cuffs and hem, and anywhere a rougher fabric (like the hook side of Velcro, or a coarse jacket lining worn over the top) has been dragging across it. Cheaper, lower-density fleeces tend to pill sooner than dense technical ones.
How to remove it. The clean fix is a fabric shaver (a battery or mains gadget that shears the bobbles off), used gently over a flat, dry fleece. A fabric comb or a fine-toothed pilling comb does the same job by hand. Work lightly and let the tool do the work; pressing hard risks catching the base fabric. Do not use a razor blade on a good fleece, it is too easy to nick the material.
How to prevent it. You cannot stop pilling entirely, but you can slow it right down:
- Wash inside out, which keeps the friction off the visible face.
- Wash cool and gentle, and avoid overloading the machine, so there is less garment-on-garment rubbing.
- Skip the fabric softener, which weakens fibres over time.
- Avoid pairing a fleece directly under or over rough, abrasive fabrics where you can.
Does fleece shrink?
Not easily. Polyester fleece is dimensionally stable and does not shrink from water the way wool or cotton can. What distorts a fleece is heat: a hot wash or, more often, a hot tumble dry can shrink, warp and mat the pile.
So the honest answer is that fleece rarely shrinks if you wash it cool and dry it low or air dry it. Follow that and shape is not something you need to worry about. Blast it with heat and all bets are off.
How often to wash a fleece
Less often than you might think. A fleece is usually a mid layer, worn over a base layer rather than against bare skin, so it picks up far less sweat and body oil than the layer underneath it.
Wash it when it actually needs it: when it smells, or is visibly grubby, or has taken a real soaking of mud. Every few outings is plenty for most people, rather than after every single walk. Over-washing does not keep a fleece nicer; it just adds wear and hastens the pilling and flattening you are trying to avoid.
Between washes, an airing does most of the work. Hang it somewhere ventilated after a walk and let it breathe.
Storing a fleece
Fleece is undemanding to store, but two habits keep it in good shape.
- Store it clean and bone dry. Sweat and grime left in the fibres over a long stint in the cupboard can set in and smell, and any damp invites a musty odour. Give it a wash at the end of the season if it has had heavy use.
- Fold loosely or hang it. Fleece does not crease or crush the way a down jacket can, so long-term compression is less of a worry, but a loose fold or a hanger keeps the loft even and stops it picking up hard creases.
A fleece is one layer in a system, so it is worth thinking about how it sits with the rest of your kit. The autumn and winter layering guide covers where the fleece fits as your mid layer, and the same care logic runs through the sister guides on washing merino base layers and reproofing a waterproof jacket.