Smartwool Classic All-Season Base Layer Review

Bottom Line

We put the Smartwool Classic All-Season through the wringer running around the Rocky Mountains and analyzing it in a controlled testing environment, and we can’t wait to put it to use on the ski mountains.

The value of this base layer is right in the name—“classic” and “all-season.” It utilizes a timeless design without overcomplicating things. The moderate warmth and excellent breathability make it an appropriate choice all year round. Smartwool is one of the oldest and most reliable companies bringing merino wool to the outdoor world to utilize its natural benefits of odor control, moisture wicking, and thermoregulation.

The main thing we love about the Classic All-Season is that it is solid across every metric instead of standing out or falling short in one particular area.

This base layer’s thin material makes it susceptible to faster wear over time. Additionally, the price tag is a little on the high side for such a lightweight and simple base layer. For more durable, synthetic base layers, check out our full list of favorites.

Comfort

The Classic All-Season is made from lightweight merino wool that lays gently on your torso without constricting in any area. As opposed to a slim, athletic fit, the Classic All-Season is more like a comfy pajama shirt.

It’s definitely a comfortable base layer that we would never hesitate to wear, but compared to other options on our list, it’s average on the comfort scale. Right out of the box, the wool is slightly itchy, but that dissipates after a handful of washings. The other thing we noticed as a brand new base layer, which will also improve as the fabric softens, is that the seams are noticeable when worn directly against the skin. The upside is that they’ve rolled over the shoulder seams to keep them out of the way of backpack straps.

The Classic All-Season fits underneath a fleece with no problem, and it can even be layered over top of a t-shirt or any other slim-fitting layer. However, when we jumped up and down, twisted, and did a little yoga with it worn as a base layer under a fleece and puffy, it did tend to wrinkle up and wedgy a bit. Again, these are minor gripes and we still choose the Classic All-Season all the time.

Warmth

It’s not the warmest base layer out there or the lightest. And that’s perfect! The middle-of-the-road warmth makes this layer such a winner. It’s not too warm to put in storage over the summer but warm enough to use as your skiing base layer.

Wool is typically warmer than synthetic fibers, and the moisture-wicking properties add a few bonus points. Wool naturally wicks moisture away from your skin and then holds it in the outer layers of the shirt as an extra layer of insulation until it dries.

The Classic All-Season is the best year-round option from Smartwool, but if you’re searching for something a little warmer, their Classic Thermal is a better option.

Breathability

Similarly to its warmth, the Classic All-Season strikes a happy medium when it comes to breathability. It retains enough heat and wicks moisture away from your skin so the wind won’t chill you to the bone. Once the moisture is wicked, the fabric allows enough of a breeze to finish the drying process.

In our controlled test of drying times, the Classic All-Season dried just as fast as the most breathable layers we tested, the Outdoor Research Echo Hoodie and the Helly Hansen Lifa Stripe Crew. However, when worn in windy conditions, the breeze is significantly less noticeable against the skin.

The Classic All-Season is a bit too warm for summer hikes in full sun, but it works great as a breathable active layer from high elevations to shoulder seasons to ski season.

Versatility

The Classic All-Season is neither too warm nor too airy, making it a suitable base layer for every season. You may have to mix up where you use it depending on the conditions – as a base layer, a hiking layer, or a sleeping layer – but we can always find a place for this shirt in any scenario.

Extra features can go a long way to increase the number of uses available for any outdoor layer. The Classic All-Season is about as simple as it gets. It would be nice to see a few more features in this layer, such as thumbholes or a zipper, but we get why Smartwool likes to keep this one simple. Smartwool does make the Classic All-Season in a quarter-zip version, bumping the breathability up a notch.

Style

Smartwool offers the Classic All-Season in eight colorways, including patterns like bi-color, heather, and a wash design. It’s not a ton, but their colors are pretty universally appealing.

We recommend going with the quarter-zip version of the Classic All-Season for a more stylish and versatile look. The crew version is super comfy with its relaxed fit, but it does look a little pajama-like.

Should You Buy the Smartwool Classic All-Season?

The Smartwool Classic All-Season is a killer value for a base layer that works all year round in a multitude of conditions. It’s warm enough to be your first layer of defense on the coldest days and lightweight enough to tackle some mid-season 14er summits. While some wool layers can be heavy and unbreathable, the Classic All-Season lets in the breeze when you need it the most. Our favorite uses for this shirt are a warmer layer during summer thru-hikes and an initial base layer throughout ski season.

While the Classic All-Seasons thrives in a wide range of scenarios, it’s not the best option on the extreme ends of the spectrum. If you’re heading out for an arctic expedition on Denali, you might want to start with a thicker base layer as your foundation. If you are hiking through Death Valley, you’ll probably want something more breathable with some sun protection. 

If you’re only going to choose one crew neck, this one could be the winner.

What Other Base Layers Should You Consider?

Patagonia Capilene Midweight Crew Review: The Patagonia Capilene is very similar to the Classic All-Season, except it is fully synthetic providing more durability and breathability. 

Smartwool Classic Thermal: The Classic Thermal is the heavier, warmer, big brother of the Classic All-Season. It offers all of the benefits of merino wool but in a warmer package and with a lot more color options. 

Icebreaker Merino 200 Oasis: While the Classic All-Season is a merino wool and nylon blend, the Icebreaker Oasis is 100% wool. It sacrifices some durability but is warmer and more odor-resistant.

Ortovox 185 Rock’n’wool Review: The Rock’n’Wool is similar in that it’s a midweight, simple wool base layer. The difference is it is 100% wool, a bit warmer, and is built with winter sports in mind.