Period-Proof Bikini Bottom

This classic silhouette looks just like any regular swim bottom and is even designed with 50+ SPF protection. Plus, it’s seawater- and chlorine- resistant, and made with our patented,  3-layer leakproof technology plus an extra layer of waterproof fabric. 

First layer: Moisture-wicking, antimicrobial technology quickly absorbs sweat and moisture while neutralizing odors to keep you fresh all day long.
Second layer: A super thin, highly-absorbent liner that holds the power of 3 tampons.
Third layer: A secure, liquid-resistant outer layer keeps leaks from happening.
Fourth layer: Another thin layer of waterproof material for extra protection.

Wear it as backup with a tampon or menstrual cup on heavier days or wear it alone on lighter days.



finally, a swim bottom you can cannonball in even when you’re on your period.
Image of a chrome heart surrounding text
Image of a absorbancy surrounding text
Holds up to 3 tampons or pads worth of blood.
Image of a moisture fabric surrounding text
Rapidly absorbs moisture to keep you fresh and dry all day.
Image of a light and comfy surrounding text
Thin, subtle, and designed to feel just like regular swimwear.
Image of a machine washable surrounding text
Simple care with mild detergent and machine wash on cold.

This classic silhouette looks just like any regular swim bottom and is even designed with 50+ SPF protection. Plus, it’s seawater- and chlorine- resistant, and made with our patented,  3-layer leakproof technology plus an extra layer of waterproof fabric. 

First layer: Moisture-wicking, antimicrobial technology quickly absorbs sweat and moisture while neutralizing odors to keep you fresh all day long.
Second layer: A super thin, highly-absorbent liner that holds the power of 3 tampons.
Third layer: A secure, liquid-resistant outer layer keeps leaks from happening.
Fourth layer: Another thin layer of waterproof material for extra protection.

Wear it as backup with a tampon or menstrual cup on heavier days or wear it alone on lighter days.



Body: 85% Nylon, 15% Spandex

Lining: 85% Nylon, 15% Spandex

Gussets: 

1. Hydrophilic + Waterproof Layer 100% Polyester with FreshFix™ Technology 

2. Waterproof Membrane Pu Film

Fabric is seawater and chlorine resistant and has 50+ SPF protection. 

Machine-wash cold, lay flat to dry. Do not bleach.

Eligible for a return or exchange within 30 days of delivery and with original sanitary strip and tags attached.

We ship our items via DHL, or Canada Post depending on your location. Please allow 1-2 business days for your order to dispatch.

For orders to Canada please allow 2-4 business days for shipping to the GTA, 3 - 10 business days for urban areas, and 6-15 business days for remote locations.

For orders to the US please allow 3-10 business days for orders to arrive.

For international orders please allow 10-25 business days.

NOTE: orders placed on Friday after 1 pm will not be processed until the following Monday.

Please see our Shipping page for more info.

FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
Nothing is TMI here—we promise.
Image of a chrome star surrounding text

All of our swimsuits have the same patented, 3-layer leakproof technology as our underwear plus an additional thin layer of waterproof material for extra protection. Here’s the breakdown.

First layer: Moisture-wicking, antimicrobial technology wicks away sweat and moisture while neutralizing odors to keep you fresh all day long.

Second layer: A super thin, highly-absorbent liner that holds the power of 3 tampons.

Third layer: A secure, liquid-resistant outer layer keeps leaks from happening.

Fourth layer: Another thin layer of waterproof material for extra protection.

KT Swimwear has a super discreet absorbent pad in the gusset liner that absorbs up to 3 tsps of blood, which equals about 3 tampons or pads.

Not always. When your flow is light, KT Swimwear can be worn alone without any additional period protection. On super heavy days,  the swimwear works great as backup protection with a tampon or menstrual cup. Every period is different though, and we recommend doing whatever makes you feel most confident.

The layers in the gusset of the underwear work to trap and absorb blood. We want you to feel 100% confident in your KT Swimwear, so if it is a super heavy flow day, we suggest wearing a tampon or menstrual cup with your suit.

Just machine-wash cold and lay flat to dry. Do not bleach.

Definitely. KT Swimwear is seawater and chlorine resistant, and has 50+ SPF protection!

If you’re not sure which size underwear to get, just book a Virtual Fitting and someone from the Knix team will video chat you to walk you through everything!

Yes. All KT Period-Proof Swim Bottoms and One-pieces are eligible for a return or exchange within 30 days of delivery and with original sanitary strip and tags attached. KT Period-Proof Swim Tops are eligible for a return or exchange within 30 days of delivery with original tags attached.

Absolutely. KT Swimwear looks and feels just like regular swimwear with a barely-there, leakproof liner.

Our styles are made to fit teen bodies. For Period-Proof Underwear in adult sizes, please visit Knix.com.

COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
Reviews
average rating 3.9 out of 5
Based on 85 reviews
  • 5 Stars
    47 Reviews
  • 4 Stars
    15 Reviews
  • 3 Stars
    5 Reviews
  • 2 Stars
    6 Reviews
  • 1 Star
    12 Reviews
76% of reviewers would recommend this product to a friend
Quality
Rated 4 out of 5
Comfort
Rated 4 out of 5
Effectiveness
Rated 4 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
85 Reviews
Reviewed by Kelly B.
I don't recommend this product
I'm a....
Parental Figure
I purchased for
A Teenager/Tween
Band Size
28"
Pant Size
Kids 8-10
Size Purchased
S
Usage
  • Pool
Rated 1 out of 5
Review posted

Not as pictured

I ordered these for my 15 yr old daughter. They are super high cut in front and cheeky in the back. They are not even close to being swim bottoms you would let your daughter wear. I paid for expedited shipping and am sadly disappointed.

Loading...
Quality
Rated 2 out of 5
Comfort
Rated 1 out of 5
Effectiveness
Rated 1 out of 5
Sizing
Rated -1 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Was this helpful?
Reviewed by Nicole
Verified Reviewer
I don't recommend this product
I'm a....
Parental Figure
I purchased for
A Teenager/Tween
Band Size
N/A
Pant Size
Kids 12-14
Size Purchased
S
Rated 1 out of 5
Review posted

Disappointed mom

The sizing appears to be a little off based on the size chart online. I ordered a small size bikini bottom swimwear for my daughter who is 11 years old. I ordered the small size based on the information in the size chart. The swimwear’s cut is way too revealing in the butt area, too much butt cheek is exposed in my opinion for an 11 year old. In general the cut of this swimwear is a little too revealing for an 11-year-old. The swimwear is also too big in the leg openings which does not allow a proper fit for my daughter and reveals her private parts. I really wanted this swimwear to work but it appears to be geared more for older girls (teens) and not a proper cut for a tween (11 yr old). I will be returning.

Loading...
Quality
Rated 3 out of 5
Comfort
Rated 3 out of 5
Effectiveness
Rated 3 out of 5
Sizing
Rated 1 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Was this helpful?
Reviewed by Amanda
Verified Reviewer
I recommend this product
Rated 5 out of 5
Review posted

My New Favorite Bottoms

I don't wear tampons. Ever. I was always scared to try them and now I'm so happy because I can go swimming on my period! I love these bottoms to mix and match with the double-scoop top!

Loading...
Was this helpful?
Reviewed by Laura
Verified Reviewer
I recommend this product
Rated 5 out of 5
Review posted

Perfect Back-Up Bikini Bottom

Great bikini bottom to have with you during vacations or in your gym bag in case your period surprises you! The black is a go-to since it goes with everything!

Loading...
Was this helpful?
Reviewed by Suzette Reid S.
Verified Buyer
I recommend this product
Rated 5 out of 5
Review posted

Period Proof Bikini

My daughter wore it this morning to swimming and it worked. I’m a super happy mommy. Stress free period swim days are here.

The period panties are also awesome just one small problem. The waist of the panties are not that strong. They work also though and I’ve already recommended them to other swim parents who have purchased

Thank you so much

Loading...
Was this helpful?