REI Co-op Active Bikini Underwear - Women's
Sweet dreams are made of moisture-wicking, fast-drying fabric that sits comfortably from the mountaintops to the track. Make the women's REI Co-op Active Bikini underwear your new essential layer.
- Bikini style features a higher rise and slightly shorter outseam than our Active Hipster underwear
- 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 post-sweat
- Pairs with REI Co-op Active bralette (not included)
- Machine wash warm; use 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 | Bikini |
| 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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Great fit, comfy fabric, weird crotch feature
Love the fit and fabric of these underwear! The fabric is smooth and light, yet feels sturdy enough. The waist band is super comfortable and lays very smoothly without any rolling or pinching. I definitely do not like the weird little pouch layer in the crotch. I don't understand this design! It is a second layer in the crotch, with the front edge left loose. The result is that it forms a kind of a pouch, and that leading edge sort of bunches and rolls, right where a woman doesn't want bunching and rolling! There is no mention of this "feature" or it's purpose in the description. Too bad, because I'd otherwise fill my underwear drawer with these panties.
Bad quality
Very comfortable but…. The fist time I wear it they started to falla apart
Seam came undone after only a few wears
Bought a couple of pairs for hiking. Would've given 5 stars, but unfortunately the seams on one pair came undone after only a few wears. Loved how comfy they were and they would've worked great for backpacking, but they aren't wearable with the seam coming apart on one of the legs.
slips and slides
These are made from a silky, comfortable fabric. The waist and leg holes are not very snug at all, so they definitely shift around a lot. I'll be happy wearing these for lounging, but running in these was experience that required me to dig deep to finish. Infer what you will...
My go-to for every day and beyond
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.
Loved them until the edging tore off
I liked these at first and got 10 pairs for travel. Sadly with in under a year 8 out of the 10 I got had come apart. The sewing of the edge of the panty on to the elastic edging comes apart and now only 2 out of the 10 are wearable and one is starting to come apart. It’s a shame because I liked them while they lasted. Waste of money.
bikini vs brief
I’m thrilled with these active underwear and how dry they stay. As a pear-shaped woman, the bikini does not contain my butt like the same size briefs do. I offer this as feedback to others with ample bottoms. I wish the briefs were in stock!!!!!!
Poor quality
I sweat horribly scrubbed in wearing a lead apron at work for hours at a time. I was hoping to find some moisture wicking and odor fighting underwear, as I am often stuck still working after I scrub out.. and not often do I have time to go change. These underwear are very thin and light, which at first seems nice, but they get stretched and don't stay in place. I washed them on the gentle cycle and the fabric looked snagged after one wash. They're incredibly poor quality, especially for the cost.
Purchased 3 pairs for backpacking and all three fell apart with unraveled seams in less than a year. They are really comfortable and pack down to nothing, but I'd suggest hand washing if you purchase.
Fell Apart
Love the fit and colors. Very comfortable. 3 out of the 4 pairs I bought fell apart (seams unraveling). One pair fell apart after the first wash. Disappointing