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Sale

Leakproof Cotton Boybrief

$28.00 CAD

$35.00

20% off
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Absorbs about 3 super tampons

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Cotton comfort

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More absorbency without bulk

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Machine washable

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| Mushroom
| Mushroom
| Mushroom
| General
| Mushroom
| General

Color: Mushroom Limited Edition

Size:

True to Size

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*
Get FREE Express Shipping on all orders $125+

Shipping

HOLIDAY SHIPPING

Give the gift of Knix! To receive your order by Dec 24th, please order by the following dates.

Toronto, Ottawa, Montreal, Winnipeg, Regina, Calgary, Edmonton, Vancouver
Standard & Expedited: Monday, December 22

Urban Centres (excluding the above)
Standard: Wednesday, December 17
Express: Sunday, December 21

Rest of Canada
Standard: Sun, December 14*
Express: Thu, December 18*
*YK, NWT, NT, NL, and remote areas across Canada.

For locations serviced solely by Canada Post, please allow at least 5 additional days due to rotating strikes. This applies to P.O Box and RR addresses.

To avoid any additional delays during the rotating strikes, we will use alternate carriers when possible.

Please note: Weather conditions and carrier issues may cause delays. Delivery dates are not guaranteed.

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.

Delivery Time
For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

Shipping Charges
Orders over $100* CAD = Free Shipping (2-6 business days)
Orders under $100* CAD = $12 CAD Shipping (1-3 business days)
Orders delivering to NWT, Nunavut and Yukon are subject to $20 delivery fee.
*After discounts, before shipping and taxes.

Year End Sale Return Policy

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 28 Points

Comfort-First Fit

A mid-rise boyshort with full coverage in the bum area.

Worry-Free Protection

An innovative floating gusset provides leak protection from every angle.

Moderate Absorbency

Absorbs about 3 super tampons worth of liquid—great for moderate flow days, light bladder leaks, and sweat.

Cozy Cotton-Blend

Soft cotton spandex feels luxurious against your skin.

OEKO-TEX® Certified

Certified according to OEKO-TEX® STANDARD 100, Product Class I : HK020 246396 TESTEX

Easy to Wash

Machine washable just like regular underwear.

Zoom

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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
FRESH FIX TECHNOLOGY®

Built-in protection that feels like nothing at all.

Absorbs about 2-3 super tampons worth of liquid.

Soft Top Layer

Soft Top Layer

Gently wicks away moisture while keeping you feeling fresh and odor-free.

4.2
Rated 4.2 out of 5 stars
Based on 227 reviews
Total 5 star reviews: 148 Total 4 star reviews: 28 Total 3 star reviews: 24 Total 2 star reviews: 9 Total 1 star reviews: 18
78%would recommend these products
ComfortRated 4.3 on a scale of 1 to 5
EffectivenessRated 4.3 on a scale of 1 to 5
FitRated 0.1 on a scale of minus 2 to 2
Ease of UseRated 4.5 on a scale of 1 to 5
227 reviews
  • Rated 1 out of 5 stars
    4 minutes ago
    Not

    Don't like at all. Remind me of granny pants.

    Bonnie H.
    Verified Buyer
  • Rated 3 out of 5 stars
    2 days ago
    Love the material

    Love the materials. Both the waistband and the leg holes are a bit tight. I probably could’ve sized up though

    Brenna G.
    Verified Buyer
  • Rated 1 out of 5 stars
    4 days ago
    1 Star

    Not a fan. Too tight around my legs. I thought they would be more like boy shorts.

    Cassandra
  • Rated 2 out of 5 stars
    5 days ago
    Not true to size

    I purchased the xs and they are way too big. The sizes seem to have gotten bigger?

    Devon H.
    Verified Buyer
  • Rated 3 out of 5 stars
    6 days ago
    Boybriefs

    I think the insert should be sewn in better I could feel the insert shifting

    Letha D.
    Verified Buyer
  • Rated 4 out of 5 stars
    6 days ago
    Leakproof Cotton Boybrief

    Love the feel and comfort of cotton!

    Sandra C.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Oh so comfortable!

    I never need to worry about protection.

    Christa H.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    5 Stars

    Love all the underwear products! Felt so good to not worry about leaking through anything during the day or at night! Definitely ordering more!

    Meg
  • Rated 3 out of 5 stars
    1 week ago
    Weirdly comfy

    These are the strangest period undies I've ever tried. I don't straight-up dislike them, but there were some weird choices made making these.

    The main fabric is really thin, which is not usually what I want in cotton, and definitely not what I'd choose for period undies. I'd want it to be a little thicker in case there was some spillage outside the leakproof area.

    I have no idea why the seams would continue all the way up the middle of your butt cheeks if the leakproof fabric doesn't. I did buy them for sleeping in, but the seams make it so I wouldn't want to leave the house in them. Though I don't feel the seams as much as I expected. They are also probably the most unflattering undies I own and somehow look like granny panties and grandpa panties at the same time. Way too high rise for me.

    They are quite comfortable though. And while I'm using them as menstrual cup backup overnight, I do appreciate that the leakproof area is only connected at each end, making it so if you wanted to add a pad for extra coverage, you'd have something to wrap the wings around.

    Jessica G.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Awesome fit and comfort

    Fits nice and very comfortable

    Bridget P.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Comfort beyond belief

    These are the best fitting and most comfortable underwear I have ever worn! I'm a woman at the age of minor urinary accidents when exercising, sneezing or laughing uncontrollably, which is why Knix are the only brand of underwear I own

    Erika C.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Love the fit

    These fit great.

    The crotch would benefit from a top layer of cotton.

    Overall I would recommend these.

    Bernadette R.
    Verified Buyer