REI Co-op Merino Bikini Underwear - Women's
Stay dry on the trail in the soft, breathable and naturally odor-resistant REI Co-op Merino Merino Bikini Underwear for women. They're made to keep you comfy throughout the day.
- Ultrafine 150 g core-spun nylon is wrapped in merino, offering a soft feel without any itchiness
- Merino wool naturally breathes, wicks away sweat, dries quickly and resists odors, making it an ideal multiday trip companion
- Flat seams and merrow-stitch construction eliminate chafing
- Soft elastic trim keeps underwear in place
- Designed to hug the body for optimum performance
- Machine washable
- Pairs with Merino Bralette and Merino Base Layer Tank Top (not included)
- Made in a Fair Trade Certified™ factory
- 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 | 48% merino wool/32% TENCEL lyocell/15% nylon/5% LYCRA spandex |
| Moisture Wicking | Yes |
| Quick Drying | Yes |
| Gender | Women's |
| Sustainability | Fair Trade Certified™ factory 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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Product looks great, but is way too big!
I ordered a medium as I always purchase the REI Co-op Active Bikini Underwear in a medium and they fit great. (Unfortunately, they have been hard to find in my size lately.) I ordered these online and when I compared the size difference to my Co-op underwear, these were like granny-panties and were huge. I didn't even need to try them on. They are going back. Positive note: The material feels nice and soft and I like the elastic material on the waistband. I might try them in an extra small.
Great for active adventures
The only issue I had with these underwear was the size was not close to what I am used to. I wear a solid size medium in just about anything sized by S, M, L, ... However, these were really big, especially in the back end. They fit fine around the waist and legs, but there was too much material in the back so they seemed to bag and get loose when I was sweating. They were otherwise comfortable, dryed quickly on the trail and there was no issues with odor at all. They fit more like a hipster than a bikini, but I liked the wide waistband and two tone design. If they were a better fit, they would be perfect.
Almost Perfect
I love the soft fabric of this bikini. I really like the colors. I got the sea forest. Fits true to size. I thought the coverage was too much for a bikini, more like a boy short. The bikini kept me feeling dry on a sunny hike. This bikini comes up too high for my liking and comfort. I'm not used to such a fit, and it didn't feel too good with the elastic at the mid-tummy. Due to that, I'm constantly aware that I am wearing it. It's definitely not the one I reach for - for hours of adventure. Less fabric, no-show seams, and a little shorter and you have your perfect bikini!
Wish these were seamless
Pros: * Extremely comfortable * Full coverage * No movement, bunching or chafing during activities Cons: * Thick seams are very visible through pants * Waistband comes up higher than my pants Would love to see a seamless version of these. They were great for lounging at home, but too visible for wearing out in public.
Finally we get some plus size merino undies!
Great undies, soft and stretchy. Seem well made, all seams look good. And I love merino - antimicrobial for the win! The only complaint I have is these give me wedgies. all. the. time. I think the butt cheeks need another inch or two of fabric to each side. I got a wide load coming though. That being said, I'll still wear them. I just have to be aware where I'm going that day, because I will be picking my seat.
Comfortable, Soft, Cute
I splurged and bought one pair of these because I was really curious about merino as an underwear fabric, and they're so great. if they weren't so expensive, I'd buy them for all of my daily wear. They're odor resistant, comfortable, and come in cute colors. I'm usually an XL or 2X and I bought a 3X and they fit great. You know underwear is great when you don't think about it at all, and that's this.
these are briefs
These are less expensive than some wool underwear so I bought them. The wool os wonderful, breathes well, dries quickly. But these are not bikini. These are briefs. Very tall. The large elastic stays put but isn’t flattering on my hourglass figure. I feel like these are a gateway pair. There a couple of dollars more affordable than others but too tall.
Inca Trail tested! Outstanding wicking undies
I find most synthetic “wicking” underwear to be nonwicking and generally uncomfortable. These wool blend undies are just fabulous. Super soft, stay in place, truly wicking, and not stinky after a day on the trail. They dry fast too so they are great for camping. I liked them so much that I bought the matching bras. Highly recommend! (The “bikini” looks huge and like a brief, but it’s the right shape to stay in place.)
Comfy and colorful
The first thing I'd like to mention is how comfortable these are, I don't even notice these are on - no weird snagging or pulling, just overall nice feeling. I do not own many wool items so am surprised at the quality of this product - not itchy, not too warm. As it is a wool product, I chose to wash by hand and air dry, and it dries fairly quickly (this would be great for a camping/backpacking trip). I will note that when I first tried it on pre-washing, the item sagged in the back, and it is more high waisted than I'm used to. It feels like it runs a bit big. After that first wash, I haven't noticed anymore sagging. I'm tempted to put it in the drier on a higher cycle than recommended to see if it shrinks up some more, but not too much (which has happened in the past with other wool items). I used these underwear while walking, doing yoga, hiking, and working a normal day. I have no complaints, they seemed invisible whilst wearing them! If you're looking for a versatile underwear to add to your closet, then this could be a good option for you.
Climbers!
These have a wonderful feel and the colors are cute, but wow do they ride up! Sort of a thong experience.