Best base layers for running

A base layer is a versatile and affordable (and we’d say pretty darn mandatory) purchase for running through the autumn, winter and spring seasons.

Base layers need to perform the dual act of keeping you warm on the run but also providing plenty of breathability and moisture wicking to stop an excessive build up of sweat.

To achieve this, the best running base layers fit close to the skin and provide ways to cool you down or allow moisture to escape, such as neck zips or mesh panels. Of course, they also need to be comfortable, so bonded or flatlock seams are preferred. See some of our favourites below.

You can also read our pick of the best running gloves and the best running gilets.

Best base layers for running in 2024

Montane Dart Thermo Zip

The Dart Thermo Zip Neck is designed to act as a winter base layer or standalone layer between seasons. It’s made of the brand’s Apex Thermo Eco recycled nylon (88%) and spandex (12%), delivering eco- credentials and durability in equal measure.

But it’s the level of comfort on offer that really makes you sit up and take notice. The brushed interior feels luxuriously soft against the skin, while the fit was spot on for this tester, sitting close against the skin without being too snug. The length of both the arms and the torso are also generous, while the seams are flatlocked, limiting any chance of irritation.

It’s incredibly warm, too, keeping us toasty when running in single-digit temperatures. When paired with an outer layer, it’s also a great base for running in sub-zero conditions. Both the close fit of the arms and the neck collar help with this, stopping any cold air sneaking. If you do find yourself overheating, though, the 1/4 zip is handy for ventilation and temperature regulation.

The Dart Thermo’s ability to wick moisture away is also worth mentioning. While the garment does pick up moisture, it doesn’t take on as much as some others we’ve tested in the past.

Verdict: A warm, high-quality garment for a very reasonable price.

Score: 87%

Gore Essential Base Layer Long

The Essential Long may be Gore’s cheapest base layer, yet it still oozes high quality, with the 88% polypropylene material feeling so soft on the skin that it also entered our casual clothing range as well.

Once out on the trails in cold December conditions, the microfibre composition was up there with Tenn, Dhb and Falke as the quickest-drying on test, and the base layer didn’t produce any nasty cold sweat patches during our runs.

Again, the top was close-fitting but didn’t restrict our arm movement. The Essential, however, was the only top on test where we felt chilly well into the run’s duration, especially on exposed stretches and tackling winds on hill tops (all the base layers were tested in similar conditions and dealt well with the cold), so we’d definitely opt for something more insulated in the depths of the winter.

Verdict: Not the warmest on test, but a fine and well-made companion for spring and autumn running, 84%

EDZ Merino Long Sleeve Base Layer

The first thing to note here is that this running baselayer is pretty basic in its design. There’s no pocket, thumb loops or reflective details, nor a neck zip.

That said, it’s made from 100% merino wool, which is known for its ability to regulate temperature. Other benefits of this fabric are that it’s naturally anti-microbial and stays warm when wet.

The garment fits true to size, too, but doesn’t sit especially close to the body. It’s comfortable on the whole, in part thanks to its flatlock seams, but doesn’t quite reach the same levels as the Montane garment.

It’s also not quite as accomplished at wicking moisture and drying off, but that’s a feature of merino wool.

In terms of the warmth that is on offer, it’ll be enough for most runners in single-digit temperatures that are layering it with another thin garment.

Verdict: A useful base layer that delivers the benefits of merino wool.

Score: 72%

Adidas Techfit Long Sleeve top

Whether it’s down to the 84% polyester/16% elastane composition or any placebo effect of wearing white, straight out of the box the Techfit Base from Adidas oozes lightness. This litheness continues onto the run with a snug yet unrestrictive feel when running, although we didn’t feel any of the purported upper-body compression benefits touted by the German heavyweights.

Adidas claims its Climalite fabric ‘sweeps sweat away from your skin’, and possibly it does this too well, as the Techfit Base remained noticeably damper and clingier once out on the trails than the Gore and Falke offerings, especially on the back region.

The perforated panels on the shoulders are successful at providing more breathability (these would’ve been a welcome addition on the back to fight the sweat patches), and the seams remained chafe-free throughout.

Verdict: Warm, well-priced and unrestrictive, but we would’ve liked more breathability, especially on there back.

Score: 82%

Falke Long Sleeve Top

We have to admit it took us a while to find Falke’s sport range on their website, as we became lost in a world of knee-high socks and men’s knitwear. Yet judging by the Long Sleeve seen here, the German brand’s lack of a sport-specific focus hasn’t impacted on the athletic quality.

Once on, the 69% polyamide/26% polyester/5% spandex composition was close-fitting but not restrictive and didn’t ride up, offering compression for those of you convinced of the upper-body benefits.

The temperature regulation is also hugely efficient, keeping us warm and free from cold sweat patches throughout. It’s also stylish enough to be worn as a single layer come the warmer months and, if that price sounds high, the quality construction should last you multiple off-seasons.

Verdict: German efficiency at its finest; a belter of a base layer for which it’s very hard to find any negatives.

Score: 94%

Artilect Boulder 125 LS

The Boulder 125 Crew is made of an ultralight Nuyarn 125 Merino fabric. Compared to standard Merino, it’s said to offer extra loft (equalling extra warmth), dry quicker and provide increased durability. It’s designed for use in autumn/spring and we’d say that’s about right.

With a 125gsm fabric, it doesn’t deliver the same level of warmth as the Dart, while a wide-cut neck also means you’re susceptible to cold draughts. In testing, the garment proved warm enough in temperatures above 10°C when worn on its own and down to 5°C when worn with a t-shirt over the top, but below that you’ll want a more substantial additional layer.

The Boulder 125 Crew breathes well, too, with a perforated mesh under the armpits providing further airflow. Moisture management appears to be on par with other Merino fabrics, drying reasonably fast and staying warm when wet. But unlike some, the fabric used here feels lovely against the skin with zero irritation.

Aside from the wide neck, the fit is good, sitting close to the body but still being reasonably relaxed. The torso and arms are some of the longest we’ve seen, ensuring good coverage, while thumb loops help keep your hands warm.

Verdict: A high-quality, comfortable base layer, but not the warmest.