REI Co-op Active Thong Underwear - Women's
Stand up to sweat in the buttery-soft REI Co-op Active Thong underwear. It wicks away moisture for hiking, running and days when the sun is your only guiding light.
- Stretchy polyester mesh is constructed with barely-there seams and trim details to keep you active and comfy
- Moisture-wicking and quick-drying for a fast recovery after sweating—and washing
- Pairs with REI Co-op Active bralette (not included)
- Machine wash warm; only non-chlorine bleach, when needed; tumble dry low
- REI Co-op brand is certified to The Climate Label; we actively fund efforts to reduce carbon emissions across our business and support climate projects around the world
Imported.
View all REI Co-op Women's Briefs| Best Use | Multisport |
|---|---|
| Underwear Style | Thong |
| Fabric | 86% polyester/14% spandex mesh |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Gender | Women's |
| Sustainability | From a Climate Label Certified brand |
| XXS | XS | S | M | L | XL | 1X | 2X | 3X | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18W | 20W | 22W | 24W | 26W | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Numerical Size | 00 | 0-2 | 4-6 | 8-10 | 12-14 | 16 | 18 | 20-22 | 24-26 | 0 | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 |
| Bust | 31 | 32-33 | 34-35 | 36-37 | 38.5-40 | 41-42.5 | 43-45 | 47-49 | 51-53 | 32 | 33 | 34 | 35 | 36 | 37 | 38.5 | 40 | 42.5 | 45 | 47 | 49 | 51 | 53 |
| Sleeve Length | 29.5 | 30 | 30.5 | 31 | 31.5 | 32 | 32.5 | 33.5 | 34.5 | 30 | 30 | 30.5 | 30.5 | 31 | 31 | 31.5 | 31.5 | 32 | 32.5 | 33.5 | 33.5 | 34.5 | 34.5 |
| Waist | 24.5 | 25.5-26.5 | 27.5-28.5 | 29.5-30.5 | 32-33.5 | 34.5-36.5 | 37.5-39.5 | 40.5-42.5 | 44.5-46.5 | 25.5 | 26.5 | 27.5 | 28.5 | 29.5 | 30.5 | 32 | 33.5 | 36 | 38.5 | 40.5 | 42.5 | 44.5 | 46.5 |
| Hip | 34 | 35-36 | 37-38 | 39-40 | 41.5-43 | 44-46 | 47-49 | 50-52 | 54-56 | 35 | 36 | 37 | 38 | 39 | 40 | 41.5 | 43 | 45.5 | 48 | 50 | 52 | 54 | 56 |
| Inseam | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 | 31 |
Sizing Notes
Measurements are stated in inches unless otherwise indicated. Size chart values represent body measurements, not garment measurements. Some women's pants are available in petite and tall sizes. Typically petite sizes fit women 4'11" to 5'3". Regular sizes fit women 5'4" to 5'8". Tall sizes fit women 5'9" to 5'11".
PETITE: Generally, as compared to regular sizes, petite sizes are 2.5 inches shorter in inseam, 1 inch shorter in body length, 1.25 inches shorter in sleeve length and ¾ inch shorter in total rise.
TALL: tall sizes are 3 inches longer in inseam, 2 inches longer in body length, 2.5 inches longer in sleeve length and 1.25 inches longer in total rise.
Capri or cropped pants have an intentionally shorter inseam—reference the technical specs instead of this chart.
Inseam is measured to the floor.
Better gear is built together
From feedback to field testing, all of our gear is dialed-in by REI Co-op members. Their adventures informed every stitch and detail—making for better, longer-lasting gear.
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So far, so good!
I've worn these twice, once for a normal day around the house and again on an afternoon trail hike with my dog. So far they feel pretty great! I was skeptical when I first got them because they're very lightweight and don't have a cotton liner (it IS lined, but it's the same sport fabric as the rest of the thong). The outer seams have this thin elastic edging sewn on which I assume helps it lay flat, but I'm anticipating it stretching out and ruffling at pressure points based on experiences with similar fabric types. All that said, while they aren't super high end, they are very very comfy and fit surprisingly well without pinching or gapping. Worth the money if you want a versatile easy-care thong.
Love these
Great balance of a nice pair of underwear for high sweat activities and a lot price point compared to a lot of other active underwear. I have 5 of the thongs and maybe 12 of the bikini style pairs. I know other people have mentioned fraying seams, but thats only happened to one of my pairs so far and I've been wearing these as my every day and active underwear for at least a year now. I wash them on the delicate cycle and try to hang them to dry, but I definitely don't always remember to do that. Plus, I wore these on my JMT week long hike, they wash up and dry like a champ hanging from the back of my pack.
good but never in stock.
I bought one pair to try out. I ended up loving these but never in stock in my size (M-L)
Need more smaller sizes available
These are my favorite; they dry quickly and so comfortable you hardly know they're there. HOWEVER, they are never available in size small or medium. WHY? Please add more stock for smaller people.
Please bring back in size S
The best underwear for athletic endeavors and day to day alike. Whenever these are available in my size I grab a few. I just wish they had them more available.
Best ever!
These are my go to panties for hiking and traveling and everything active. They’re so comfortable that I forget I’m even wearing them. Please bring back smaller sizes!!
When are these coming back??
I love this underwear, they're extremely breathable and comfortable. I've had several pairs of these for years and they've lasted. When are they coming back??
Only Active Thong I wear!
Love this thong and have it in the "Active fabric" as well as the Merino. I was concerned at first that it wouldn't stay in place as there is no elastic at the top of the band but it Stays right wear I put it and doesn't shimmy down when hiking- Working out or doing Yoga. I stopped wearing all my other active thongs
Quickly fell apart
I liked this underwear, but after a few washes the stitching quickly started unraveling on both pairs that I bought.
Great for a little while
I love these at first. They're super comfortable and breathe well. However, they don't hold up incredibly well, even when I never put them through the dryer.