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Home / Swim One-Pieces / Classic One Piece Swimsuit

Classic One Piece Swimsuit

$110.00 USD

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Full coverage

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Sporty scoop neckline

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Premium UPF 50+ fabric

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Machine washable

| Black
| Black
| Black
| Black

Absorbency: Essential

Essential
Drop
Drop
Drop
Drop
Drop
No Absorbency
Light
Drop
Drop
Drop
Drop
Drop
about 1-3 regular tampons

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

Returns

Returns

Sale & Last Call

Items discounted 30% and below are eligible for size exchange or store credit. Items discounted above 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.

Free Returns

Knix covers the return shipping fees for exchanges and refunds initiated through our Return & Exchange Portal. Exchange orders initiated through our Return & Exchange portal are also eligible for free shipping within the USA and Canada. Please note, the shipping fees on your original order are non-refundable.

Return Policy

Return policy varies by product, please check if your item is refund or exchange eligible by viewing our full policy here.
Rewards Members Earn 110 Points

"This swimsuit combines comfort, coverage, and confidence"

- Women's Health

Swim in Style

A fit we've spent years perfecting.

Sun-Smart Protection

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

Feels Made For You

Thicker, adjustable straps make it adaptable for different torso lengths. It features a shelf bra with removable cups and full bum coverage.

Zoom

| Black
| Black
| Black
| Black

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

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4.5
Rated 4.5 out of 5 stars
Based on 136 reviews
Total 5 star reviews: 99 Total 4 star reviews: 18 Total 3 star reviews: 11 Total 2 star reviews: 3 Total 1 star reviews: 5
88%would recommend this product
ComfortRated 4.6 on a scale of 1 to 5
FitRated -0.0 on a scale of minus 2 to 2
SupportRated 4.2 on a scale of 1 to 5
Write a Review (Opens in a new window)
136 reviews
  • Rated 5 out of 5 stars
    1 week ago
    Super comfy

    Never wear a one piece because I feel like they make me look like a toddler, but I feel pretty good in this one piece. I just had a baby this past year and needed a one piece that my boobs don’t pop out of. This is it. It’s comfy and covers my bits. I feel good. I bought my underwear size and would say that I should have gone down a size. It fits but I wouldn’t mind if it was a little snugger on my bits.

    Kate O.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Love it

    Fit is just right!

    Claire M.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    One piece swimsuit

    I really like how it fits and how comfortable it is

    Mary H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    N/a

    N/a

    Libby P.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Love it!

    It’s comfortable and stylish..

    It’s a double layer so it does take a bit longer to dry!

    Pam K.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Swimsuit

    It will be nice under a coverup. Fits nice.

    NOEL T.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    one piece swimsuit

    Haven't had an opportunity to use my new swimsuit yet but I know it will be perfect for me! The fit is great and I love the colour.

    Janet B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    5 Stars

    It is buttery smooth and fits me so well. One-pieces can be not so cute but this is cute and fits so well

    Julia
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    Another Knix win

    Love how thick the material is and for once I actually feel supported in a bathing suit. Would definitely reccommend!

    Caitlin E.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    5 Stars

    This is my second one of these exact swimsuits and i will likely purchase a third! I tell everyone to buy a knix swimsuit.

    Brittany
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    Beautiful classic suit

    Love this suit . Quality is suberb. Fit is amazing. Love the cups for support. Beautiful classic suit!!

    Cindie S.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    Very comfortable

    Super comfortable and supportive. I have a short torso, so it was a little long but not as bad as others.

    Jenn S.
    Verified Buyer
    Was this helpful?