Trail Performance, Loungewear Comfort: Black Diamond Alpine Light Pants Review

By the time I stumbled into camp after an 8-hour push over Paintbrush Divide, I was beat — sunburned, salty, and soaked from a combo of sweat and creek crossings. The last thing I wanted to do was change clothes. So, I didn’t. I choked down yet another bar and crawled into my sleeping bag, still wearing the Black Diamond Alpine Light Pants.

And, honestly? I slept like a rock. That’s how airy these pants are. Built for movement but soft enough to pass for pajamas, they carried me through steep climbs, surprise storms, and snow-covered trails, and then doubled as sleepwear without a second thought. 

The Alpine Lights are far more technical than your favorite pajamas, so comfort is where the comparisons end. These pants are breathable, soft to the touch, built to last, and designed with thoughtful features sure to please climbers, hikers, and mountaineers alike. 

In short: Black Diamond Alpine Light Pants are so versatile that they blend trail performance with loungewear-level comfort. Lightweight, stretchy, and breathable, they’re ideal for everything from alpine scrambles to long backpacking days. A soft, wide waistband, weather-resistant finish, and smart additions like adjustable hems and harness-friendly pockets make them a standout for three-season adventures. Just don’t expect the zip pocket to fit your phone.

Compare the BD Alpine Light Pants with other picks in our guide to the best hiking pants for women.

Black Diamond Alpine Light Pants Review

Performance in the Field

Though specifically designed with climbers in mind, these pants have quickly become my go-to for everything from epic day hikes to alpine overnights. The woven four-way stretch fabric offers exceptional mobility, allowing me to step, scramble, and climb without restriction. Whether I’m tackling steep switchbacks or navigating rocky terrain, the pants move with me, never against me. 

One standout feature is the wide, stretch-knit waistband, which feels more like leggings or high-end loungewear than a piece of alpine gear. It lies flat under a hip belt or harness and eliminates bulk or bunching. 

During an early-season backpacking adventure along the Teton Crest Trail, which included a trek up and over the snow-covered Paintbrush Divide in Grand Teton National Park, I found this waistband extremely comfortable. Even while carrying a heavy pack, it felt almost unnoticeable.

Others we tested, including the Patagonia Women’s Terravia Peak Pants, have seams, buttons, and belts that tend to dig into my hips and abdomen, leading to discomfort and difficulty breathing. This waistband has none of those irritating features. It allows for a comfortable fit, making it easy to forget you even have high-performance pants on at all.

Weather Resistance and Durability

Conditions on this hike included everything from blazing sun and light rain to creek crossings, snowfields, and exposed ridgelines. Through it all, the Alpine Light Pants held up impressively well. The PFC-free DWR finish shrugged off water and wind, and the fabric dried quickly after getting damp during an afternoon drizzle. At 10,000 feet in June, you never know what weather to expect, so having reliable, weather-resistant pants that can adapt is essential. 

I also appreciated the cord-lock adjustable hems, which let me cinch the cuffs tight to keep out debris and snow or customize the length for different footwear. Despite pushing through brush, sliding on rock, and plenty of aggressive scrambling, the fabric resisted tears and snags, something many ultralight pants struggle with.

Packability and Style

At just under 10 ounces and compressing down to the size of a frozen breakfast burrito, the Alpine Light Pants are a minimalist’s dream. They pack easily into any backpack, making them a reliable just-in-case option for unpredictable shoulder-season hikes or high-elevation routes where conditions can change quickly.

Yet despite their ultralight build, these pants don’t look or feel like purely technical gear. The sleek, slim silhouette and wide range of color options make them trail-to-town ready. I often wear them straight to the brewery or a friend’s house for a post-hike barbecue. I will admit that more than once, I’ve forgotten that I’m wearing hiking pants. 

Pockets and Storage

Functionality extends to the pockets as well. The Alpine Light Pants come with two front drop-in pockets, a back drop-in pocket, and a zippered thigh pocket. All are accessible while wearing a harness, a thoughtful touch for climbers and mountaineers. Our only gripe is that we wish the zippered thigh pocket were bigger. 

Room for Improvement 

While the Alpine Light Pants shine in comfort, mobility, and versatility, there’s still a bit of room for refinement. That zippered thigh pocket isn’t quite deep enough to fit my smartphone, which is odd given that I use an older, smaller model than many people. A roomier pocket would go a long way. 

While not necessarily a con, since these are built for three-season use, it’s worth noting that while the lightweight fabric excels in warmer conditions, it isn’t built for frigid alpine starts or windy summits unless paired with a base layer, puffy pants, or rain pants. Choose the beefier BD Alpine Pants if you’re looking for something warmer. That being said, these are ideal for shoulder season hikes. For instance, we use them almost exclusively when there’s still snow on the ground, but you can feel spring just around the corner. 

Black Diamond Alpine Light Pants Review: The Bottom Line

For hiking, scrambling, climbing, or backpacking, the Black Diamond Alpine Light Pants hit the sweet spot. They’re the perfect combo of lightweight, stylish, high-performance gear. Whether I’m bagging peaks or lounging in camp, these pants deliver unmatched all-day comfort, exceptional mobility, and surprising durability in a sleek, low-profile package that I actually enjoy wearing.