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Home / Bikini Underwear / Leakproof Cotton Bikini
Best Seller

Leakproof Cotton Bikini

$25.00 USD

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Absorbs about 3 super tampons

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Breathable cotton comfort

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More absorbent without the bulk

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Machine washable

Gabrielle has 48” hips and wears a Knix size XXL | Pepper

Gabrielle has 48” hips and wears a Knix size XXL

| Pepper
Gabrielle has 48” hips and wears a Knix size XXL | Pepper

Gabrielle has 48” hips and wears a Knix size XXL

Gabrielle has 48” hips and wears a Knix size XXL | Pepper

Gabrielle has 48” hips and wears a Knix size XXL

| General

Gabrielle has 48” hips and wears a Knix size XXL

Absorbency: Moderate
Drop
Drop
Drop
Drop
Drop

Color: Pepper

Size:

True to Size

•

Size:

Size and Fit Guide

Free Shipping on orders $100+

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Processing Time

Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order.

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For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

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Orders over $100* USD = Free standard Shipping (4-8 business days)**
Expedited = $4.99 USD (3-6 business days)**

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Expedited = $9.99 USD (3-6 business days)**

*After discounts, before shipping and taxes. Processing times not included in estimates.
**Military Addresses Excluded. Standard Military Address Shipping = $10.00 USD (est. varies per location)
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Items discounted below 30% are eligible for size exchange or store credit. Items discounted 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.
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Comfort-First Fit

Bikini silhouette with a classic mid-rise fit and medium hip and bum coverage.

Worry-Free Protection

An innovative floating gusset provides leak protection from every angle.

Moderate Absorbency

Absorbs about 3 super tampons worth of liquid—great for moderate flow days, light bladder leaks, and sweat.

Cozy Cotton-Blend

Soft cotton spandex feels luxurious against your skin.

OEKO-TEX® Certified

Certified according to OEKO-TEX® STANDARD 100, Product Class I : HK020 246396 TESTEX

Easy to Wash

Machine washable just like regular underwear.

Zoom

Gabrielle has 48” hips and wears a Knix size XXL | Pepper
| Pepper
Gabrielle has 48” hips and wears a Knix size XXL | Pepper
Gabrielle has 48” hips and wears a Knix size XXL | Pepper
| General

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Everyday Wear
  • • No leakproof protection
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    about 8-14 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 4-7 super tampons
  • cup
    about 1.5-3 menstrual cups

Light

Drop
Drop
Drop
Drop
Drop
  • • light period days
  • • sweat
  • • discharge
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

Drop
Drop
Drop
Drop
Drop
  • • moderate period days
  • • light bladder leaks
  • • sweat
  • tsp
    about 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

Drop
Drop
Drop
Drop
Drop
  • • extra heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    about 15-20 tsp
  • pad
    about 1.5-2.5 super pads
  • tampon
    about 7-11 super tampons
  • cup
    about 2-3 menstrual cups
FRESH FIX TECHNOLOGY®

Built-in protection that feels like nothing at all.

Absorbs about 2-3 super tampons worth of liquid.

Soft Top Layer

Soft Top Layer

Gently wicks away moisture while keeping you feeling fresh and odor-free.

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4.5
Rated 4.5 out of 5 stars
Based on 163 reviews
Total 5 star reviews: 124 Total 4 star reviews: 14 Total 3 star reviews: 9 Total 2 star reviews: 9 Total 1 star reviews: 7
85%would recommend this product
ComfortRated 4.5 on a scale of 1 to 5
EffectivenessRated 4.5 on a scale of 1 to 5
FitRated 0.1 on a scale of minus 2 to 2
Ease of UseRated 4.7 on a scale of 1 to 5
Write a Review (Opens in a new window)
163 reviews
  • Rated 4 out of 5 stars
    3 minutes ago
    Leakproof cotton bikini

    Love the style I should have ordered a size bigger and I need a bit more aborbancy for bladder leaks

    Charlotte C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    7 hours ago
    5 Stars

    This goes for all the products in the package. I love Knix‘s leakproof underwear however, I think I prefer the cotton over the shiny material, but this is the first time that I’ve tried this out or that it’s been offered.

    Stephanie
    Was this helpful?
  • Rated 5 out of 5 stars
    7 hours ago
    5 Stars

    This goes for all the products in the package. I love Knix‘s leakproof underwear however, I think I prefer the cotton over the shiny material, but this is the first time that I’ve tried this out or that it’s been offered.

    Stephanie
    Was this helpful?
  • Rated 5 out of 5 stars
    7 hours ago
    5 Stars

    This goes for all the products in the package. I love Knix‘s leakproof underwear however, I think I prefer the cotton over the shiny material, but this is the first time that I’ve tried this out or that it’s been offered.

    Stephanie
    Was this helpful?
  • Rated 5 out of 5 stars
    2 days ago
    Amazingly Comfortable

    These are my favorite of the three styles I purchased. I really like the cotton fabric. It's soft, fits well, and stays in place- no wedgies or leaks. They are great for light days or as a back up coverage if also using tampons.

    Christa R.
    Verified Buyer
    Was this helpful?
  • Rated 2 out of 5 stars
    6 days ago
    Disappointed, not the same as no-show styles

    Wanted to switch to cotton for more breathable options but these are not the same as the seamless no-show styles from Knix. The seams are very thick and the gusset absorbent pad is as thick as a heavy flow maxi pad. It definitely feels like you’re wearing a diaper and it shows if you’re wearing leggings or anything tight. I decided to keep anyway because I do like cotton but I would only wear these under very loose pants or dresses/skirts and only on heavier flow days. I wish Knix would show the pic of what the gusset looks like on their product page so everyone can see what they’re getting.

    Winnie
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    I've never been so happy with underwear

    I've been a Knix fan for many years, and swear by their leak proof undies. That said, I could not possibly be more impressed with these. They're incredibly comfortable, absorbent enough that I don't feel like I'm wearing a wet diaper all day, and really a lovely underwear experience. Thanks for the upgrade, Knix!

    Anon
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    5 Stars

    Liked these so much I ordered 3 more!

    Susan
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    5 Stars

    Great improvement with the cotton briefs from my last order. Comfy and well made. Will buy as again.

    Angela
    Was this helpful?
  • Rated 2 out of 5 stars
    1 week ago
    floating gusset

    I ordered a 6 pack of large on sale. I did not expect how the liner would be free from the actual panties on the sides. The fit is fine but when I'm just walking, I feel like they need to be adjusted. I don't like wearing them and I can't return them.

    Marlenna
    Verified Reviewer
    Was this helpful?
  • Rated 1 out of 5 stars
    2 weeks ago
    Very uncomfortable

    The seams are thick and very uncomfortable when sitting or walking. They aren't digging in (I'm wearing my regular size) but I feel them throughout the day. They're also very noticeable under pants and jeans. I wasn't expecting them to be shaped slightly differently than the regular leakproof bikini underwear. Not sure if that's the reason they shift/move during normal daily activities but that's also an issue. I ordered these because I wanted to switch to a cotton version of the leakproof bikini for my workouts but can't imagine wearing them during cardio.

    Holly
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    Very comfortable!

    Pretty colours. Fit wonderfully.

    Kim H.
    Verified Buyer
    Was this helpful?