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  • Soft and warm merino wool naturally resists odor, wicks moisture away and dries fast
  • Fabric offers protection from UV light with a rating of UPF 50+
  • Flatlock seams help eliminate chafing
  • Machine washable; line dry or dry flat in shade
  • The women's Icebreaker Oasis long underwear leggings have a slim fit


View all Icebreaker Women's Long Underwear Bottoms

REI membership


Best Use Multisport
Fabric Merino wool
Sun-Protective Fabric Yes
UPF Rating 50
Moisture Wicking Yes
Quick Drying Yes
Underwear Weight Lightweight
Inseam (in.) 27.5 inches
Gender Women's

Size chart

Sizing notes

Measurements are stated in inches unless otherwise indicated. CHOOSING THE RIGHT SIZE: If your body measurements are midway between two sizes, select the smaller size for a tighter fit or the larger size for a looser fit. If your body measurements result in different sizes, we recommend using your chest measurement for tops and your hip measurement for pants.

Rated 4 out of 5 by from Initially disappointed, but excellent warranty. I wrote the earlier review about holes appearing in my Oasis leggings. I was pleased to be contacted promptly afterwards with information about the warranty (which I hadn't known about) and I was promptly able to process a claim for them. Knowing that I can get a replacement if I have issues pretty much fixes my problem, and I am glad to know that Icebreaker stands so firmly behind their products. My leggings (and my daughters) are fast-drying, look great, feel great, and they are comfortable to wear and move around in. If you want clothes for use and reuse day after day with only a hotel room to wash and dry in, these are your babies.
Date published: 2015-10-01
Rated 2 out of 5 by from Did not last two months. I had two pairs of Oasis leggings delivered on July 7th, and it is now August 19th, just over a month later. One of my pairs is fine, but the other inexplicably has two holes in the butt - not even along the seam, where I might expect holes. I am very disappointed, as they feel fantastic, and fit really well. I am 5'2", 165lbs, got an XL, and they are just a little loose. The material is soft and light, and I've worn these for quick-dry road trip pajamas, rollerskating, and hiking, and they've kept me warm/cool by turns and wonderfully comfortable. Unfortunately, I just can't justify buying more with this price tag when they get holes so easily.
Date published: 2015-08-19
Rated 5 out of 5 by from Amazing base layer for backpacking I wasn't sure whether to get the 200gm base layer or the 260gm for three season backpacking in the Canadian Rockies. I opted for the 200gm after trying them on in store and I am very glad I made that choice. These leggings are very comfortable for sleeping in a -7°C rated sleeping bag at temperatures falling below 0°C (there was frost on my tent); the following morning, I began my hike wearing these leggings under my pants and was not uncomfortably warm even after a steep 5 km climb. These are definitely the best base layer I have ever owned, and I highly recommend them!
Date published: 2013-09-12
Rated 4 out of 5 by from Outerwear, not just Underwear I have these leggings in the black strip version. They are super cute just as leggings and warm too! I do think they are a little more itchy than other pairs of Merino wool leggings that I have had, but I have yet to throw them in the wash. I have worn them several days and again, no stink as another reviewer mentioned. There was another review saying that they fit slightly low-rise and I would have to agree. The waist band does slide down a little when bending over or kneeling. I purchased a medium and maybe would have been better with a large, but the only size they had in store was the medium and they were just so cute I had to have them!
Date published: 2015-12-01
Rated 3 out of 5 by from New, not improved I have a pair of older style leggings, and definitely noticed the changes in the "new and improved" fit. I am 5'10", 160 lbs, and after consulting the sizing chart, ordered a Large. The baggy "mom-jean" fit is gone, however the new cut is shorter in the waist and now creating a double whammy: "camel-toe" and "muffin-top". The leggings also are a bit short, above the ankle bone. Having long legs, I'm used to that, however I'm not sure I can live with the muffin top profile. I was hoping to wear them over tights and under tunics as leggings...can anyone suggest an alternative that fits high-waisted, long-legged gals??
Date published: 2014-10-25
Rated 5 out of 5 by from Awesome~ly skimpy So... I love these pants. They are super thin, warm, fit under my Levi's skinny jeans when going out, snow pants in the hills and are fantastic for sleeping in your unheated house when its cold. I can only imagine they will serve me well whilst ice climbing. Liked 'em so much I went rock climbing in them, but was told by my climbing partner that WAY too much of my crotch was highlighted by the thin material... Apparently they are underwear? Need to remember this...
Date published: 2013-12-17
Rated 4 out of 5 by from Consider intended use and size before purchasing These leggings run a bit larger than expected. 5'5 120lb and I normall wear a small-medium in things but had to return for a size down. I live an active lifestyle cycling most places, which requires a lot of stretch and pull on the fabric. I don't think this particular item is up to the task of sports that require a lot of extended body movement. They might hold up to lighter sports, but really your best bet is to pick the Pace legging, which is stronger due to the seaming. These are very, very warm and comfy. I wear them in San Francisco for the winters. I like them but would have chosen another model of legging. If you are a person who spends all their time in leggings as a fashion and comfort issue, you will probably like these. I cannot wear synthetic leggings because they start to feel itchy and painful after a few hours, but I can wear these for a full day and have rarely felt uncomfortable.
Date published: 2014-01-25
Rated 5 out of 5 by from Love Them I agonized over if I should get a small or medium. I'm 5'6'' and 148lbs. I wear a size 6 pant but after 3 babies in 3 and half years, I have a flabby midsection and I hate when stretchy pants sit too low or too high (under ribs). These hit just in the right spot and I got the small (although, I suspect a medium would have been fine too. They're definitely snug). They're a bit shear....I wouldn't wear them without a long enough top to fully cover your rump. And they definitely aren't long. The leg opening sits about an inch above my ankle bone. I also like that I can bend over and not have the slide down "plumber-style". The only thing I'd change is I wish they were about an 1.5'' longer, but I would still buy them regardless.
Date published: 2013-12-19
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