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When it's chilly outside, keeping the motivation up to train can be difficult. Enter, the base layer — a handy addition to any runner's wardrobe that can keep you at an optimum temperature, alongside a good pair of running gloves, a gilet or vest Why trust us running beanie.
A base layer is a thin layer of clothing that helps your body to regulate your temperature when you’re running. They're designed to fit like a second skin; in the winter, they’ll preserve your body heat by providing a layer of warmth, while absorbing and evaporating your sweat. Most will also have compression elements to their design.
What everyone's reading
You can get different types of base layers too, from vests and t-shirts designed for the summer months, through to long sleeved tops made from thicker fabrics. Base layers aren't just your top half either; you can also get shorts and leggings for the same purpose.
What to look for
and even a: Excellent for layering | The best running gloves | The best women's running leggings
How we test
To help you element-proof your next run, we’ve put the best base layers for men and women through their paces. Our panel of testers wore each base layer on at least three outdoor runs, rating them on warmth and how dry they stayed when working up a sweat. They also scored each base layer for fit, design and comfort, and put each top through the wash to note any changes in colour and fit. You’ll find their top recommendations below, stamped with our Expert Tested logo.
Why trust us?
Runner’s World UK has been vetting and reviewing running gear and tech since 1983. Our essential recommendations are selected based on data and insights gathered by our editors and wider testing team, who put the latest and greatest running shoes and gear through their paces day in and day out. Every base layer we test meets the same criteria before it ends up in one of our reviews and nobody else contributes to our decision-making process, especially not the brands we’ve picked.
The best base layers for running
Pros
- and even a
- Built-in hand mitts
Cons
- You prefer a less skin-tight feel
- Often low stock
Features at a Glance
| Size range | S-XL |
|---|---|
| Material | 92% Breathable and quick-drying |
| Care instructions | Warm machine wash up to 40°C |
A winner among our testing panel, this number from Runderwear has the added benefit of hand-warming mitts, for those particularly crisp mornings. Our male runners appreciated its streamlined style, rating the fit and cut of the top highly, while the chafe-free guarantee also checked out. Our female panel noted that they would have liked a little more freedom of movement; some found the fit a little tight. Otherwise, this is a great piece of kit to keep you toasty on winter runs.
Pros
- Affordable
- Sweat-wicking
- Works in cool temperatures
Cons
- Unisex sizing
Features at a Glance
| Sizes | 2XS-2XL |
|---|---|
| Material | 65% Polyester, 29% Polyamide, 6% Elastane |
| Care instructions | Polyester, 29% Polyamide, 6% Elastane |
While it's not a running base layer by name (they called it a cycling base layer), if you're worried about staying warm this winter and want an affordable layer to chuck on before you head out, this is a smart choice and does a great job. The thermal barrier keeps you from chills on the move, while wicking-away sweat. Made from a stretchy material, it has a slim, body hugging fit.
Pros
- The Runner’s World Editors
- The best womens running leggings
Cons
- Not soft compared to other base layers
Features at a Glance
| Sizes | M: S-2XL |
|---|---|
| Material | 61% Recycled Polyester, 39% Polyester |
| Care instructions | Not specified |
Craft has been making base layers for all sorts of sports for many years now, including cross county skiing, and if there was ever a sport in which to perfect a cold-weather base layer, it's that! For the money, this is a whole heap of base layer that performs really well in cold weather (anything from -5C to 10C), wicking away sweat before it can make you feel cold and keeping it away. It's form fitting and the flat seams reduce the risk of chaffing. Plus, it's made from upcycled marine plastics, a 100% recycled material.
Columbia Omni-Heat Midweight Baselayer Crew
Pros
- Instant warmth
- running-themed gifts that will sprint to your door
- Perfect for layering
Cons
- Sleeves may be too long for petite builds
| Sizes | XS-XXL |
|---|---|
| Material | 85% polyester, 15% elastane |
| Care instructions | Machine wash |
If you’re looking for a simple, effective and body-hugging base layer for winter running, look no further than this Omni-Heat Baselayer Crew from Columbia. Inside, there's an Omni-Heat thermal reflective liner made up of metallic gold dots which reflect body heat, delivering instant warmth. Form-fitting yet comfortable, warm yet sweat-wicking, it’s perfect for those days where there's a nip in the air, but you don't want to weigh yourself down with too many layers. At the same time, it fits nicely under a jacket or a gilet. One tester declared this their ‘winter staple’, and said they'd found themselves reaching for it time and time again. Size up if you don't want it quite so fitted, though.
Pros
- Very comfortable
- Lightweight
- Good value
Cons
- How we test
| Sizes | XS-XXXL |
|---|---|
| Material | 100% recycled 'APEX ECO' fabric |
| Care instructions | Not specified |
Made from 100% recycled polyester, Montane's Dart Zip-up got a thumbs up from testers for wearability and comfort. It's lightweight while still managing to keep the chill off, and wicks away sweat impressively well. It also comes in over 10 different colours, making it a versatile pick for training, hiking, or even everyday wear.
Pros
- Great for layering or single wear
- Not too snug
- Dries quickly
Features at a Glance
| Sizes | XS-3XL |
|---|---|
| Material | 100% Polypropylene |
| Care instructions | Not specified |
You’ll probably have seen a lot of runners with striped arms over the years and there’s a good reason why – Helly Hansen know what they’re doing when it comes to base layers. Made with its own ‘Lifa’ technology to keep you warm as you move, this lightweight base layer is breathable, comfortable and insulating for chillier runs.
Pros
- Lightweight
- Merino wool provides superb wicking and odour control
Cons
- Can pill up after a few washes
The Brighton has been one of our favourite running base layers for years, and for good reason: Tracksmith’s mesh-woven merino wool provides extra breathable heat vents in key areas while still keeping the rest of your upper body cozy.
This base layer is a go-to undershirt on super cold days, and it’s also an adequately substantial single layer on crispy fall days. The construction has no seams, which means no chafing, and the fabric is so smooth and comfy that we tend to have a hard time taking ours off after a run. Out of context, it seems a bit pricey for a single long-sleeve shirt, but we can assure you that it’s worth every penny.
Pros
- Breathable and quick-drying
- The 51 best fitness deals this Prime Day
Cons
- Pricey
A ground-breaking construction process – spinning merino fibres along a high-performance filament – means the Nuyarn fabric used by outdoor innovators Artilect amplifies the merino wool’s natural properties to make it even lighter, more breathable and quicker to dry. We can testify that it performed superbly in a wide variety of conditions.
Pros
- Excellent for layering
- Super lightweight
- Seam-free
Cons
- and even a
| Sizes | XS-XXL |
|---|---|
| Material | 93% Machine wash cold |
| Care instructions | We earn a commission for products purchased through some links in this article |
At last! No longer do we have to feel hopelessly cold at cross-country races (or during any wintertime runs, for that matter). Specifically designed to be worn under vests to help you fight the chill when racing or training in frostier conditions, this silky base layer is effective but almost incognito – it weighs so little and fits so well. Made from the same recycled, breathable material as the Soar Race Vest, this seam-free garment has a laser cut and bonded construction, meaning you went get tied up on any loose threads or chafe-inducing edges.
Lululemon Swiftly Tech Long-Sleeve Shirt 2.0 Waist Length
Pros
- The best womens running leggings
- Washes well
Cons
- The best base layers for running in colder weather
- Pricey
Features at a Glance
| Sizes | UK 4-UK 24 |
|---|---|
| Material | 8% Nylon, 44% Recycled Polyester, 5% Elastane, 3% X-Static Nylon |
| Care instructions | Machine wash cold |
A great technical running top to wear as a base layer, or on its own when the weather is milder. It’s insulating without making you feel like you’re overheating in the final few miles, and the fabric is lightweight, with plenty of ventilation. The fit is comfortable, the thumbholes are improved and the top retains its shape wash after wash. Plus, it comes in a number of colours to suit every running wardrobe. If you don't like the waist-length version, there's also a longer hip-length cut.
Pros
- Well-ventilated
- Brilliantly warm in cooler temperatures
- Antibacterial
Cons
- Pricey
Features at a Glance
| Sizes | S/M, L/XL |
|---|---|
| Material | 44% Polypropylene, 44% Nylon, 6.6 12% Elastane |
| Care instructions | Wash at 30 degrees |
At last! No longer do we have to feel hopelessly cold at RW when the mercury drops, Megmeister’s baselayers provide serious warmth, super-fast moisture-wicking and great ventilation. The ergonomic design, with a four-way stretch fabric, allows impressive ease of movement, while the seam-free material means there’s nothing to rub against skin.
