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Home / Teen Period Swimwear / Teen Period Swim Bikini Bottom
Best Seller

Teen Period Swim Bikini Bottom

$45.00 USD

Absorb about 3 regular tampons

Lower to mid-rise fit

Medium coverage style

Premium UPF 50+ fabric

Machine washable

Rose (she/her) has 35

Rose (she/her) has 35" hips and is wearing a size M

| Black
Rose (she/her) has 35

Rose (she/her) has 35" hips and is wearing a size M

| Black

Rose (she/her) has 35" hips and is wearing a size M

Absorbency: Moderate

Color: Black

Size:

True to Size

•

Size:

Size and Fit Guide

Free Shipping on orders $100+

Shipping

Shipping

Processing Timelines

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. Once an order is placed, we cannot guarantee any address updates, order changes or cancellations. Orders placed on Friday after 1PM will not be shipped until the following Monday.


Split Shipments

Most orders will ship from a single warehouse. However, we occasionally ship from a combination of warehouse locations, so you may receive your order in multiple parts. If items from your order ship in separate packages, we’ll send you tracking information for each package when it becomes available.

Delivery Timelines

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines do not include processing times. See above for details. All transit times are measured in business days which are Monday-Friday, excluding holidays.

Please note, all shipping timelines are estimates and are not guaranteed.

We are not able to ship to US territories (including Puerto Rico, U.S. Virgin Islands, Guam, Northern Mariana Islands and American Samoa) at this time.
Easy Returns within 30 Days

Clothing & Swim

Returns & Exchanges

Leggings, sweats, t-shirts, sleepwear, and swim items are eligible for return or exchange within 30 days of delivery with tags attached. Swim bottoms and pieces must have the original sanitary strip intact.

Still have questions? View our full policy here.
Rewards Members Earn 45 Points

Product Description

The perfect blend of swim style and protection. Upgrade your summer wardrobe with the Teen Period Swim Bikini Bottom, featuring a flattering silhouette and premium UPF 50+ fabric for extra sun safety. These bottoms are crafted from chlorine-resistant, quick-dry material that keeps its shape and color all season long. Whether you’re lounging by the pool or heading to the lake, this sustainable period swim solution offers a comfortable, modest fit that looks exactly like a classic bikini bottom.

Swim in Style

Classic cut and swim collection staple. Lower to mid-rise with mid-cut leg and medium bum coverage.

Worry-Free Protection

Discreet, built-in protection that absorbs about 3 regular tampons worth.

Sun-Smart Protection

UPF 50+ fabric protects your skin while you soak up the sun.

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Rose (she/her) has 35
| Black
Rose (she/her) has 35
| Black

How to Choose?

Essential

  • • Days you don’t need leak protection. Everyday freshness and moisture wicking.
  • tsp
    0 tsp

Heavy

  • • Extra peace of mind. For the first days of your cycle, light bladder leaks, or a full night's sleep without a leak.
  • 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

  • • Daily freshness. For sweat, discharge, period spotting, or backup protection.
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

  • • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
  • 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

  • • Ultimate peace of mind. For the heaviest period days, light bladder leaks, unexpected postpartum flow, or overnight protection.
  • 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

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LEAKPROOF SWIM WORKS IN LAYERS

Built-in protection that feels like nothing at all.

Looks just like regular swimwear. Non-swelling liner and patented no-show design.

Top Layer

Smooth and comfortable liner in swimsuit fabric.
4.7
Rated 4.7 out of 5 stars
Based on 123 reviews
Total 5 star reviews: 104 Total 4 star reviews: 8 Total 3 star reviews: 4 Total 2 star reviews: 2 Total 1 star reviews: 5
What our customers are saying
Customers say these swim bottoms provide reliable comfort and confidence during water activities. Many reviews mention the natural look and comfortable fit, though some note sizing can run small. The bottoms look like regular swimwear and stay securely in place during swimming, beach activities, and water sports. Common feedback includes praise for the quality material and stylish design. While most find them effective, a few users mention fit adjustments were needed.
92%would recommend this product
ComfortRated 4.7 on a scale of 1 to 5
FitRated -0.2 on a scale of minus 2 to 2
EffectivenessRated 4.5 on a scale of 1 to 5
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Usual Pant Size - Knixteen
Usual Pant Size - Knixteen
Size Purchased - Knixteen Underwear
Size Purchased - Knixteen Underwear
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123 reviews
  • Rated 5 out of 5 stars
    3 weeks ago
    Love love

    My daughter absolutely loves the knix swimwear and underwear

    Kaila S.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    1 month ago
    Perfect

    Ordered 2 for my daughter, she loves them they look like normal bottoms not thick and feel nice! Happy with this purchase!

    Julia T.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    1 month ago
    Purchased for teen

    This set is so cute

    Loniann F.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Great product

    Works well while swimming but rides up the back a little

    Kaitlyn H.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    2 months ago
    Works great!

    Works great for my daughter.

    Shannon T.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    3 months ago
    Super useful!

    Fits under my daughter’s regular one piece.

    Elizabeth S.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    Fun in the sun!

    Bought for my daughter. She wore it on a recent trip and didn’t require the leak proof part at the time… but bottoms were so comfortable for her that it didn’t matter. She usually wears S underwear in Knix, but M bathing suit bottoms. S are too snug so suggest sizing up.

    ABel
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 4 out of 5 stars
    8 months ago
    Bikini bottoms

    Great item. Only thing to look out for is when they are wet and you sit on a towel they will leak through.

    Kate I.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    8 months ago
    period swim bottom review

    Fit perfectly and were good for all day use at the beach

    Emily G. G.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    8 months ago
    Best fit ever

    My teen continues to love these swim products! So easy to wash, perfect fit and material.

    Cynthia A.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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  • Rated 5 out of 5 stars
    8 months ago
    Period Swim bottoms

    The material is excellent and my daughter loves the cut and feel of these SWIM bottoms. She is 13 and wears size Small and it flatters her body. Now she can swim even on those "moon days!" True, it's not perfect because on heavy days some liquid runs down her leg but when that happens she has more reason to jump back in the lake!

    Cheryl A.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
    Was this helpful?
  • Rated 5 out of 5 stars
    9 months ago
    So comfy

    Best swimwear ever

    Mia F.
    Verified Buyer
    Reviewing
    Teen Period Swim Bikini Bottom
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