1. The Quick List ↴
2. Best Overall: Soar Merino & Silk Base
3. Most Versatile: Montane Dart Long Sleeve T-Shirt
4. Most Comfortable: Tracksmith Brighton Base Layer
5. Warmest: Under Armour OutRun The Cold LS
6. Best For Racing: Soar Race Base
Base layers are among the most essential pieces of winter running gear. They sit tight against the skin to help keep you warm while also wicking away sweat so you don’t end up a sticky mess 20 paces into a run. The best base layers will be warm without feeling oppressive, and ideally use some kind of odor-resistant fabric to reduce your running laundry pile, which I find always grows during the winter months.
How I Test Base Layers
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I usually run 50-70 miles a week and this continues right through the winter months, with January and February often a key training period ahead of a spring marathon. I live and train in the south of the UK where the winters are fairly mild, but I wear a base layer for pretty much every run once the temperature drops below 50°F (10°C), allowing me plenty of opportunities to test them.
The Quick List
Below you’ll find more detailed reviews of all my base layer picks, but here’s a quick look at the top options available. Click on any base layer to jump to the full review.
Best overall
The Soar Merino & Silk base is soft on the skin and naturally odor-resistant. It works as a base layer or your only layer on milder days, and you can get a long- or short-sleeved version of the top.
Most versatile
The Dart top resists odors and has a comfortable, loose fit which means it works as a standalone top as well as a base layer, especially because it offers UPF20+ protection for sunnier days.
Most comfortable
This seamless top is designed to be more breathable around the core and warmer on the sleeves to help with temperature regulation and keep you comfortable. The mostly Merino fabric is soft and it’s available in a range of colors.
Warmest
My go-to option for running in sub-zero temperatures, this cozy base layer is seriously warm and has a clever slit in the sleeve that allows you to see your running watch without rolling the sleeve up and exposing your skin to the frosty air.
Best for racing
This extremely lightweight base provides warmth without any restriction or fears of overheating, making it perfect for winter races when you can’t face wearing just a vest or T-shirt. It’s also great for fast training sessions as a result.
The Best Base Layers For Runners
Best Overall
The Merino and silk fabric used in this base is as comfortable as it sounds, which is to say very comfortable indeed, and the Merino wool naturally resists odours and wicks sweat away from your body. Soar makes the base layer as both a T-shirt and a long-sleeved shirt, so you can pick one to suit your preferences, and the fit is not too tight so you can use it as your only layer during milder weather.
Most Versatile
A pleasingly versatile and comfortable long-sleeved top that you can use all year round, Montane’s Dart works well as a base layer in colder conditions or as a standalone tee on milder days. As well as offering UPF20+ protection, the fabric is made from 100% recycled polyester and treated with Polygiene, which means you can use it multiple times before it starts to smell.
Most Comfortable
The knit on this top is tighter on the sleeves and more open around the core, to provide the perfect balance of warmth and breathability so you’re never chilly but you don’t overheat. The top is mostly made of Merino wool to keep odours at bay, and comes in a range of stylish designs. Tracksmith’s tops are cut for skinny runners and we found going a size up on our normal running gear produced the best fit.
Warmest
The OutRun The Cold works as both a base layer and a top, but we found we enjoyed wearing it most when used as the latter during a freezing spell in the UK where our runs were consistently done in sub-zero temperatures. If it’s milder then it works well as a standalone top – when it’s warm you’ll get sweaty trying to use it with another layer.
One neat feature is the slit on the left sleeve that allows you to see your watch while keeping your hands covered with the thumb-hole sleeves. This allows easy access to your stats on the run and your watch to track your heart rate using the optical sensor without exposing any skin to the elements.
Best For Racing
Many runners, myself included, face a dilemma when winter races roll around. If I just wear a vest I get very cold, especially early in the race. The alternative is to wear a base layer under my club vest, but this can be too warm or feel restrictive when you’re running hard.
The Soar Race Base solves the dilemma. It’s a featherweight layer made from the same material as Soar’s race vest. It provides just enough warmth to take the edge off and ensure you aren’t shivering on the start line, but is light enough that it won’t cramp your style when you’re in full flight during the race.
More Running Gear
- The best men’s running tops that bridge the gap between T-shirt and jacket and keep you comfortable in cool weather
- Our top picks for the best men’s running jackets – both waterproof and water-resistant – so you can head out whatever the weather
- Keep your legs toasty all winter with the best men’s running tights
- Cosy gear and tips for winter running so even the worst weather won’t worry you
