Period Swim Freestyle One-Piece

Tuck Dives. Cannonballs. Lazy rivers. This leakproof swimsuit works as hard as they do. Both sporty and cute, it not only stops leaks, but fits like a glove, and offers a comfier, greater range of motion.


On light days, they can wear it alone. On heavy days, they can use it as backup with a tampon or menstrual cup.

Absorbency: Medium

Key features:

- Feels just like regular swimwear

- Bum coverage: Medium

- Thin & undetectable period-absorbing gusset

- Anti-slip racerback straps for added mobility

- No shelf bra or padded cups for reduced drag

- 50+ UPF protection

- Fully lined

Sleek, supportive, leak-fighting protection—all in one-piece.
Image of a absorbancy surrounding text
Holds about 3 regular pads’ worth of blood
Image of a seawater resistant surrounding text
Designed by the former Canadian Olympic Apparel Designer
Image of a light and comfy surrounding text
Thin, discreet, and feels just like regular swimwear
Image of a no shelf bra surrounding text
No bra pads for a smoother, closer fit

Tuck Dives. Cannonballs. Lazy rivers. This leakproof swimsuit works as hard as they do. Both sporty and cute, it not only stops leaks, but fits like a glove, and offers a comfier, greater range of motion.


On light days, they can wear it alone. On heavy days, they can use it as backup with a tampon or menstrual cup.

Absorbency: Medium

Key features:

- Feels just like regular swimwear

- Bum coverage: Medium

- Thin & undetectable period-absorbing gusset

- Anti-slip racerback straps for added mobility

- No shelf bra or padded cups for reduced drag

- 50+ UPF protection

- Fully lined

Machine wash cold with mild detergent, do not bleach, lay flat to dry.


Body: 85% Nylon, 15% Spandex

Lining: 85% Nylon, 15% Spandex

Gusset: Leakproof Technology®, PU Film 


Additional Product Ingredient Information

For items with a 20% or more discount, you may exchange for another item or return for store credit. No refunds can be accommodated. 

Items marked as “Flash Sale” or “Clearance” are final sale, meaning no returns, exchanges or refunds can be accommodated. No exceptions. 

Please note: Sale items are not eligible for our First Pair Risk-Free Policy.


We offer free standard shipping on all orders over $70. We ship our items via DHL or Canada Post depending on your location. Please allow 1-2 business days for your items to be processed and shipped. During high volume periods, your order may take up to 7 business days to dispatch from our warehouse location.


US Orders: Please allow 3–10 business days for orders to arrive.

International Orders: Please allow 10–25 business days for orders to arrive.

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

CANADIAN CUSTOMERS: Shop www.knixteen.ca to order in Canadian currency.

 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.

Our period swim bottoms contain a triple-layer gusset that absorbs your flow and locks in leaks, whether you're in or out of the water. When they go in the wash with detergent, the blood releases through the top layer—leaving your swimwear fresh and clean for next time. Yes, your other clothes will remain stain-free!

Here's the breakdown of our 3-layer leakproof technology:

Layer 1: A silky-smooth top layer that sits comfortably against the skin.

Layer 2: A highly-absorbent middle layer designed with our leakproof technology to absorb up to 1-3 tampons worth of period blood.

Layer 3: A waterproof outer layer prevents swelling. 

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

Machine wash cold and lay flat to dry. Do not bleach, iron, or dry clean.

Check out our size chart here. 

Yes! All of our regular price swim bottoms and one-pieces are eligible for a return or exchange within 30 days of delivery, as long as the original sanitary strip and tags are attached. Our swim tops are eligible for a return or exchange within 30 days of delivery with original tags attached.

Absolutely! The leakproof liner built into all of our period swimwear is undetectable, so they look and feel just like regular swimwear.

Our styles are made to fit teen bodies. For period swimwear in adult sizes, please visit Knix.

 COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
JUST PLAIN BETTER
Reviews
average rating 3.9 out of 5
Based on 47 reviews
  • 5 Stars
    27 Reviews
  • 4 Stars
    4 Reviews
  • 3 Stars
    7 Reviews
  • 2 Stars
    4 Reviews
  • 1 Star
    5 Reviews
70% of reviewers would recommend this product to a friend
Quality
Rated 3 out of 5
Comfort
Rated 4 out of 5
Effectiveness
Rated 3 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
Write a Review
Review posted
Reviewed by Leanne Y.
Verified Buyer
Period Swim Freestyle One-Piece
Reviewing
Period Swim Freestyle One-Piece
Band Size
34"
Pant Size
Teen 4-10
Size Purchased
M
Usage
  • Pool
  • Swim Class
Rated 5 out of 5

Perfect for my active teen!

My daughter wanted a suit for swim team. This one works great for practice or meets when on her period.

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Effectiveness
Rated 5 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
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Review posted
Reviewed by Amber V.
Verified Buyer
Period Swim Freestyle One-Piece
Reviewing
Period Swim Freestyle One-Piece
Band Size
N/A
Pant Size
Teen 00-2
Size Purchased
XS
Usage
  • Pool
  • Beach
Rated 5 out of 5

My daughter LOVES this!

My daughter loves this bathing suit! The fit is perfect, the color is flattering, and you can't tell it's a period bathing suit. I'm very happy with this bathing suit and will definitely continue to purchase more bathing suits from KT by Knix!

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 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
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Review posted
Reviewed by Tsugumi K.
Verified Buyer
Period Swim Freestyle One-Piece
Reviewing
Period Swim Freestyle One-Piece
I'm a...
Adult
I purchased for...
Myself
Pant Size
Teen 4-10
Size Purchased
M
Band Size
N/A
Rated 5 out of 5

Fit small

I got this for myself. I feel it fit smaller than other style but still like it.

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 4 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
Effectiveness
Rated 3 out of 5
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Review posted
Reviewed by Tsugumi K.
Verified Buyer
Period Swim Freestyle One-Piece
Reviewing
Period Swim Freestyle One-Piece
I'm a...
Parental Figure
I purchased for...
A Teenager/Tween
Pant Size
Kids 8-10
Size Purchased
XS
Band Size
N/A
Rated 5 out of 5

Good quality

I got this for my 13 y old daughter. It’s a second one. she loves it.

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I recommend this product
Quality
Rated 5 out of 5
Comfort
Rated 5 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
Effectiveness
Rated 3 out of 5
Was this helpful?
Review posted
Reviewed by Susan P.
Verified Buyer
Period Swim Freestyle One-Piece
Reviewing
Period Swim Freestyle One-Piece
Rated 5 out of 5

Awkward Swim Classes no more!

Takes the awkward out of swim classes when your teen has her period. Wish I had this when I was younger!

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