Long sleeve or short sleeve? Zips or no zips? Bright and colourful or classic monochrome? Choosing the finer design elements of your workout gear can be great fun, and even motivate you to get out there and show off your athletic prowess (as well as your swanky new threads). But when it comes to choosing the best base layer for you, the first and most important thing to consider is the most basic: the fabric, and what it can do.
Does it need to offer UV protection if worn alone? Will it be comfortable worn next to the skin? Is it warm enough for the climate you typically work out in? Does it need high-performance wicking? There are two types of materials that really shine in the best base layers: merino wool, and synthetics such as polyester and polypropylene.
Ultra-fine, ultra-soft merino keeps its original bearers, a fluffy breed of alpine sheep, warm on wintry mountaintops and cool when the snow melts in spring, and it can do the same for you. It naturally offers UV protection, shielding you from the sun on high-altitude hikes. Plus, its antibacterial — and, it follows, anti-odour — properties mean you can wear the same layer day after day, reducing the need to wash more, buy more, or pack more.
Polyester and other common sweat-wicking synthetics, on the other hand, have their own very useful set of qualities. Synthetic base layers tend to dry a little quicker, feel a little lighter, and cost a little less than merino. The only problem is that they aren’t as warm as wool, but this makes them ideal for exercising in warmer climates or on sunnier days, when an extra defence against chilly winds isn’t necessary.
1. Helly Hansen Warm Ice Women's
Distinctive design from a distinguished name in women's outerwear
Best for: Regular use | Material: 57% merino wool / 43% polypropylene
The all-round winner on our list of technical tops, the Warm Ice Crew from Helly Hansen is a clever mix of merino wool exterior and Lifa fibre (polypropylene) interior. As such, it performs all the duties you’d expect with none of the drawbacks, combining the warmth of wool and the wicking properties of synthetic fibres for a seemingly super-powered under-layer. It also comes in an attractive range of colours and patterns, with distinctive contrast stitching to stand out on your next run.
2. SKINS Women's DNAmic Short Sleeve Top
This short-sleeve tee fits like a second skin
Best for: Sport fanatics | Material: 76% polyamide (nylon) / 24% elastane (spandex)
SKINS have long been a go-to for compression sportswear, but the DNAmic range takes that reputation and really runs with it. The Dynamic Gradient Compression in this short sleeve base layer supports and stabilises throughout upper body exercises, keeping your core and back in optimum form, and making it great for HIIT, resistance training, and endurance exercise. Internal silicone grip prevents the top from riding up while you’re doing your thing, and the mesh airflow panels keep you from overheating. For comfortable compression, look no further.
3. dhb Aeron Women's Merino Base Layer
Light as a cloud, warm as your favourite woolly jumper
Best for: Value for money | Material: 65% merino wool / 35% polyester
Sleek and stylish enough to be part of an everyday outfit, this dhb Aeron base layer is a joy to wear whether exercising or relaxing. Lightweight, fine, and soft, thanks chiefly to its mix of merino and polyester, it keeps you comfortable when you’re working hard, but fights the chill when you’re cooling down. It also washes well and keeps its flattering shape, a common concern when it comes to wool-containing tops.
4. Icebreaker Vertex Turtleneck
High-tech and high-style, these aren't your Grandma's thermals
Best for: Skiing | Material: 100% merino wool
The classic stylings of this charming thermal turtleneck make it just as comfortable kicking back après-ski as keeping you warm on the slopes. Complete the set with the snazzy matching leggings for maximum cosiness on very cold days, or rock it as a warming mid-layer. Wherever you wear it, the lightweight, soft and stretchy 260gm merino construction will offer reliable warmth while still allowing a range of movement.
5. Montane Women’s Primino Long Sleeve T-shirt
Our first-choice long-sleeved layer for lower temperatures
Best for: Icy cold weather | Material: 50% merino wool / 25% PrimaLoft / 25% polyester
The woolly warmth of fine-fibred merino, the fast-acting wicking of high-tech PrimaLoft — it’s a match made in heaven in this long sleeve base layer from Montane. Intended for high levels of activity in low temperatures, it draws up sweat and wicks it away quickly to keep you dry and comfortable, and the sleek, form-fitting design is engineered for maximum comfort and durable flexibility.
6. Sherpa Dikila Zip Tee
Comfortable and protecting for high-altitude adventures: it's yippee for the zip tee
Best for: Hiking | Material: 82% nylon / 18% polyester
As its brand name would suggest, the Sherpa Dikila Zip Tee has our vote for best base layer for climbing, hiking, or mountaineering. It has a UPF (Ultraviolet Protection Factor, to you and me) of 50+, so you can avoid burns even at high altitudes, and the flat-locked sleeve seams reduce chafing from pack-straps. The smooth interior and useful zip neck make for easy on-and-off even over other base layers, which can be notoriously grippy, and the soft exterior makes for great insulation.
7. Kari Traa Rose Half Zip Top
Up with the lark? On with the wool. This warming base layer is great for winter.
Best for: Multi-activity lovers | Material: 100% merino wool
This wonderfully warming 100% merino base layer is just the ticket for early morning runs and winter walks. Not only will it shield you from chilly penetrating winds, the half-zip neck makes it easy on, for a quick start (especially helpful when dark mornings make it harder to get out of bed) and easy off, for a quick change post-workout. It’s also a really good-looking piece of kit, in a distinctive design and range of cheerful colourways. We’re especially taken with the teal tile and contrasting coral, ourselves.
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