Period Swim Short

Our most-requested swim style ever! Perfect for teens who want fuller coverage in the front and back—while being fully protected on their period. Wear it alone on light days, or with a tampon or menstrual cup on heavy days.

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 about the same as 2-3 super tampons worth of period blood.

Layer 3: A waterproof outer layer prevents swelling.

Other Features:

- Bum coverage: Max

- Wide waistband for comfort

- Mesh interior lining

- Super discreet liner

- 50+ UPF protection

- Pair with matching Double Scoop Bikini Top

Finally! Max-coverage, period-proof swim shorts that have your back.
Image of a absorbancy surrounding text
Absorbs about the same as 2-3 super tampons worth of period blood.
Image of a moisture fabric surrounding text
Rapidly absorbs moisture to keep you fresh and dry.
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
Simply machine wash cold and lay flat to dry.

Our most-requested swim style ever! Perfect for teens who want fuller coverage in the front and back—while being fully protected on their period. Wear it alone on light days, or with a tampon or menstrual cup on heavy days.

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 about the same as 2-3 super tampons worth of period blood.

Layer 3: A waterproof outer layer prevents swelling.

Other Features:

- Bum coverage: Max

- Wide waistband for comfort

- Mesh interior lining

- Super discreet liner

- 50+ UPF protection

- Pair with matching Double Scoop Bikini Top

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


Body: 85% Nylon, 15% Spandex

Lining: 85% Nylon, 15% Spandex

Gusset: Leakproof Technology®, Polyurethane 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 4.3 out of 5
Based on 259 reviews
  • 5 Stars
    171 Reviews
  • 4 Stars
    45 Reviews
  • 3 Stars
    17 Reviews
  • 2 Stars
    9 Reviews
  • 1 Star
    17 Reviews
85% of reviewers would recommend this product to a friend
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Review posted
Reviewed by Stefanie S.
Verified Buyer
Period Swim Short
Reviewing
Period Swim Short
Rated 5 out of 5

Great product!

We recently exchanged the twist high waist bottoms for these shorts and they are really great quality, comfortable, and they fit my 11 year old daughter really well! I love that Knix makes sizes for younger girls because a lot of the period swim wear out there is made for teenage girls or adults. I also love that they have the swim shorts option because sometimes the other bottom styles can be too revealing. Love these!

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Reviewed by Elfie S.
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Period Swim Short
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Period Swim Short
Rated 5 out of 5

Excellent fit!

These were a great purchase for my daughter!

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Comfort
Rated 5 out of 5
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
Effectiveness
Rated 5 out of 5
Ease of Use
Rated 5 out of 5
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Reviewed by Sheryl J.
Verified Buyer
Period Swim Short
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Period Swim Short
Rated 5 out of 5

Swim sure bottom

Good quality just not the right size had to exchange it for a larger size

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Reviewed by GRETCHEN M.
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Period Swim Short
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Period Swim Short
Rated 5 out of 5

My kids' favorite swim bottoms

Both of my kids love these and use them all the time. They love having swim bottoms that cover their butts. We did choose a medium based on the smaller-bodies sizing and that worked well for a girl who is normally a women's size small or even xs.

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Reviewed by Ashley F.
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Period Swim Short
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Period Swim Short
Rated 5 out of 5

Swim Short

Great coverage for teen. My daughter says it’s very comfortable. We have not had the opportunity to swim yet, but it looks like it will hold up well.

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