Hiking fleeces and midlayers: reviews and buying guide
The fleece is the layer that does the quiet work between your base layer and your shell: it traps the warm air your body makes, keeps working when it is damp, and lets sweat pass through so you are not soaked from the inside. This hub covers the whole midlayer, from thin grid fleeces you wear on the move to high-loft warm fleeces and the active-insulation pieces in between, with the fabrics explained, how to choose for UK conditions, and full reviews of the ones we rate.
13 reviews
Patagonia Better Sweater Review: Jacket vs 1/4 Zip
The Patagonia Better Sweater is the smart, sweater-knit fleece that looks as good in the pub as on the hill. Here is the difference between the Full-Zip Jacket and the 1/4 Zip, the women's cut, and the one honest thing to know before you buy.
Patagonia R1 Air Review: The Benchmark Active Fleece
The Patagonia R1 is the fleece the entire active-midlayer category is measured against, and the R1 Air is its airier, more breathable evolution. Here is what it does, the difference between the Full-Zip Hoody and the Zip-Neck, and who should buy it.
Best women's hiking fleeces and midlayers UK 2026
A short, honest guide to the best women's hiking fleeces and midlayers in the UK for 2026: which of our top picks come in a women's cut, how women's fit differs, and the one I would buy first.
Best hiking fleeces UK 2026: grid, midweight, warm fleece and technical picks
The fleece is the layer that does the quiet work between your base layer and your shell, and the right one changes how a whole day feels. Here are the best hiking fleeces for the UK in 2026, sorted by type, from light grid fleeces you wear moving to the high-loft warm fleece you pull on when you stop.
Arc'teryx Delta Hoody review: the grid fleece I actually wear the most
I own the Arc'teryx Delta Hoody (the old Delta LT, in Polartec Classic 100 micro-grid velour) and it is the fleece I reach for more than any other. Here is what it is like to actually live in, where it shines, and the one thing it is not.
Salomon Thernova Fleece Hoodie review: active insulation for the stop-start day
The Thernova is a PrimaLoft active-insulation hoodie built for the swing between working hard and standing still, and it is high on my shortlist for Finland. Here is the case for and against.
Mammut Aconcagua ML review: a Power Stretch Pro fleece, judged on the specs
The Aconcagua is Mammut's Polartec Power Stretch Pro fleece: a slim, stretchy, breathable active midlayer. A close look at who it suits, and where the slim Euro fit and premium price bite.
Columbia Steens Mountain fleece review: the budget best-buy, judged honestly
The Steens Mountain is the cheapest credible cosy fleece from a major brand, and it sells by the container-load on Amazon. A close look at what your money actually buys.
Craghoppers CO2 Renu Fleece review: the value fleece with a conscience
The CO2 Renu keeps turning up as the UK best-value fleece, and it does it with recycled and bio-carbon fibre at a price the technical brands cannot touch. Here is my researched take on what you get, and what you give up, for around £80.
Rab Nexus Fleece review: the grid midlayer that earns its keep on the move
The Rab Nexus is a UK favourite lightweight grid fleece: Thermic G, strong warmth-for-weight and it breathes well. A clear look at what it is and, just as important, what it is not.
Montane Protium fleece review: which Protium is the warm one?
The Protium is Montane's packable warm fleece, and it is the best UK-brand answer to the high-loft midlayer. But Protium is a family, not one jacket, and the name hides three quite different fleeces. Here is which one you actually want.
The North Face Denali fleece review: the warm-fleece benchmark, judged on the specs
The Denali is the fleece every other high-loft warm fleece gets measured against. What the Polartec 300 pile actually buys you, where it wins, and the three things it will never do.
ThruDark Phalanx Fleece review: their best-known piece, judged as clothing
The Phalanx is ThruDark's longest-serving design and the piece most people associate with the brand. I own one, bought at retail. Here is what £240 of Polartec High Loft actually gets you.
What a fleece and a midlayer actually do
The fleece, or midlayer, is the layer that manages your temperature on a walk. Your base layer moves sweat off your skin, your shell keeps the weather out, and the layer in between traps the warm air your body makes while still letting that moisture pass through to escape. Get it right and you barely notice it. Get it wrong and you spend the day either boiling on the climbs or shivering the moment you stop.
For our ranked picks by type, from the best all-round midlayer to the warmest fleece and the best budget buy, see the best hiking fleeces roundup. There is also a women's fleeces and midlayers guide.
Fleece or midlayer: what is the difference?
The two words are often used for the same thing, and mostly they are. A fleece is a knitted or brushed polyester fabric that traps air in its pile. A midlayer is the broader job: any layer worn between your base and your shell for warmth. Most midlayers are fleeces, but not all. Active-insulation pieces, the ones built around PrimaLoft or Polartec Alpha, use a light synthetic fill instead of a fleece pile to give more warmth for the weight while still breathing when you move. We cover both here, because for a UK hiker they do the same job in the layering system.
Grid, high-loft and solid fleece
Fleece comes in three broad types, and the type matters more than the brand. A grid fleece has a waffle-like inner face that traps warm air in the squares while the channels between them dump heat and moisture fast, which makes it the breathable one you wear while working hard. A high-loft fleece has a deep, plush pile that holds a lot of air, so it is the warm one you pull on when you stop. A solid, flat-faced fleece sits between the two: cosy and cheap, warm at rest, but heavier for its warmth and less breathable on the climb. Most walkers are best served by a grid fleece for everyday use, with a high-loft fleece added for cold, low-output days.
Fleece fabrics explained
A few fabric names come up again and again. Polartec Power Grid is the benchmark grid fleece, light and breathable with a gridded back. Polartec Thermal Pro covers the warmer, higher-loft fabrics. Polartec Power Stretch is a close-fitting, stretchy, more wind-resistant fleece with a smoother face, good as a slim technical layer. PrimaLoft and Polartec Alpha are active insulations rather than fleeces, giving warmth for very little weight. Own-brand fabrics from Rab, Montane and Mountain Equipment are often close equivalents of these, so judge a fleece on its type and weight rather than the marketing name.
How to choose: warmth, weight, fit and features
Start with the job. If you want one do-everything layer for changeable UK days, a grid fleece or a light active-insulation midlayer is the versatile choice. If you feel the cold when you stop, add a high-loft warm fleece rather than buying one heavier fleece that is too warm to walk in. Beyond that, a hood adds real warmth and wind protection for very little weight, a deep chest or full zip lets you dump heat fast, and a slim cut layers more cleanly under a shell. Weight and packability matter if you carry the fleece more than you wear it. Fit matters most of all, because a fleece only traps air well when it sits close without being tight.
How to wash and care for a fleece
Fleece is easy to look after and lasts for years if you treat it right. Wash it inside out on a cool, gentle cycle with a liquid detergent, and skip the fabric softener, which clogs the pile and kills the warmth and breathability. Never tumble dry it on heat and never iron it, because fleece is polyester and will melt. To slow down pilling, do up the zips and wash it with smooth fabrics rather than rough hook-and-loop straps. A well cared-for fleece will outlast several waterproofs.
Where a fleece sits in your layering system
Think of your layers as a system, each with one job: base layer for moisture, fleece or midlayer for active warmth, insulated jacket for standing-still warmth, and a shell for the weather. A fleece is neither waterproof nor windproof, so it works best under a shell when the weather turns, not instead of one. In deep cold it is one part of the stack rather than the whole answer: below a certain temperature you add a down or synthetic jacket over the top for the standing-still warmth a breathable fleece cannot give.
For the layers either side of the fleece, see our base layers guide and waterproof jackets guide.