FREE Shipping on orders over $80 CAD / $70 USD

Menu

Underwear By Absorbency
Light
Drop
Drop
Drop
Drop
Drop

Absorbs 1-3 regular tampons
Moderate
Drop
Drop
Drop
Drop
Drop

Absorbs 2-4 super tampons
Heavy
Drop
Drop
Drop
Drop
Drop

Absorbs 4-7 super tampons
Leakproof Explained
Learn More
5 Reasons to Wear Leakproof
Sleepover Boxer

Sleep Sleep

Your cart’s feeling a little empty.

But the perfect pair is waiting.
Continue Shopping
You Might Also Like
| Black
Travel Bag
$20.00 CAD

Holds up to 7 pairs of undies

Color: Black Limited Edition

Size:

Size:

Suggestions

Top Picks

Super Leakproof® Sleepover Boxer

$45.00 CAD
Mix, Match & Save

Color: Blue Stripe Limited Edition

+1

Period Emergency Kit - Bikini

From 
$40.00 CAD
$47.00
Best Savings

Period Swim Full-Coverage Bikini Bottom

$55.00 CAD
Mix, Match & Save

Color: Blue Coast Limited Edition

+3

Super Leakproof® Sleepover Short

$45.00 CAD
Mix, Match & Save

Color: Night Sky Limited Edition

+2
Home / Moderate Absorbency / Leakproof UltraThin No-Show Boyshort
Mix, Match & Save

Leakproof UltraThin No-Show Boyshort

$25.00 CAD

Buy 3+ SAVE 15%
Checkmark

Absorbs about 2.5 super tampons

Checkmark

Invisible under clothes

Checkmark

Superior protection without the bulk

Checkmark

Machine washable

| Red Tulip
| Red Tulip
| Red Tulip
| Red Tulip
| General
| General
| General
| General
| General

Absorbency: Moderate

Moderate
Drop
Drop
Drop
Drop
Drop
about 2-4 super tampons
Light
Drop
Drop
Drop
Drop
Drop
about 1-3 regular tampons
Heavy
Drop
Drop
Drop
Drop
Drop
about 4-7 super tampons

Color: Red Tulip Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*

Build Your 3-Pack

| Red Tulip

Leakproof UltraThin No-Show Boyshort

Color: Red Tulip Limited Edition

Size:

Size:

| Red Tulip

Leakproof UltraThin No-Show Boyshort

Color: Red Tulip Limited Edition

Size:

Size:

| Red Tulip

Leakproof UltraThin No-Show Boyshort

Color: Red Tulip Limited Edition

Size:

Size:

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.

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. 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.

Canadian Orders

Orders within Canada will be shipped with Canada Post or Purolator based on your address and carrier availability.

Standard Canadian shipping is free on eligible orders over $100 CAD*. Orders under $100 CAD are $12 CAD for standard shipping. Orders delivering to NWT, Nunavut, and Yukon under $100 CAD* are $20 CAD for standard Canada shipping.

*After discounts, before shipping and taxes
First Pair Risk-Free Policy

First Pair Risk Free for 30 Days

First Pair Risk-Free Policy

Because they’re, well, underwear, we can’t accept exchanges or returns on used items. BUT you can try your first pair on your first order risk-free for 30 days!

If you ordered the wrong size of period underwear, we’ll send you a different pair at no cost or offer you a standard refund* within 30 days of delivery (excluding original shipping fees).

If your order included multiple period underwear, open, wash, and wear one pair only. That way if you don’t love them, any unopened packages from the same purchase will be eligible for an exchange or a standard refund* (excluding original shipping fees).

All unopened packages will be donated to local organizations to support people in need.
“My daughter loves boyshorts better than bikini only because they fit well under her uniform and she feels they give more coverage. She loves the leakproof ultra thin no-show underwear! She feels confident wearing them and is happy I found them for her.”

- Jackie V.

You May Also Like

Leakproof UltraThin No-Show Bikini

$25.00 CAD

Super Leakproof® Sleepover Short

$45.00 CAD

Super Leakproof® No-Show Boyshort

$29.00 CAD

Comfort-First Fit

Boyshort silhouette with a mid-rise fit and extra hip and bum coverage. Designed specifically for teens and tweens, so may fit smaller than styles made for adults.

Worry-Free Protection

Our newest leakproof innovation provides more absorbency without the bulk. Patented 360 LeakSeal™ technology locks in leaks at every edge.

Absorbency Level: Moderate

Absorbs 2.5 super tampons worth of liquid—perfect for moderate flow days, light bladder leaks, and sweat. The carbon cotton gusset top layer keeps you dry.

Discreet

Made from our signature buttery-soft fabric and designed to be invisible under clothes, including leggings.

Easy to Wash

100% reusable and machine washable, just like regular underwear.

Zoom

| Red Tulip
| Red Tulip
| Red Tulip
| Red Tulip
| General
| General
| General
| General
| General

How to Choose?

Heavy

Drop
Drop
Drop
Drop
Drop
  • • Perfect for overnight protection or your teens heaviest days when changing into a fresh pair might not be convenient.
  • 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
  • • Ideal for lightest period days, spotting, sweat and 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
  • • Ideal for medium period days, discharge and 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
  • • Ultimate peace of mind. For the heaviest period days 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
LOVED BY TEENS. TRUSTED BY PARENTS. 

Why leakproof?

Built-in protection that helps teens feel secure on their period. The science behind the #1 Leakproof Brand in North America.

Soft Top Layer

Soft top layer

Comfy, super smooth moisture-wicking liner keeps you feeling fresh and dry.

Easy to Wash

100% reusable and machine washable, just like regular underwear.

Explore Best-Sellers

Shop All Arrow Right

Leakproof UltraThin No-Show Bikini 3-Pack

$65.00 CAD
$75.00
Bundle Deal

Color: Pastel Wings/Pink Orchid/Blush Limited Edition

+6

Super Leakproof® Sleepover Short

$45.00 CAD
Mix, Match & Save

Color: Night Sky Limited Edition

+2

Period Swim Sport One-Piece

$99.00 CAD
Mix, Match & Save

Color: Black Limited Edition

+2

Super Leakproof® Sleepover Boxer

$45.00 CAD
Mix, Match & Save

Color: Pink Stripe Limited Edition

+1

Period Emergency Kit - Bikini

From 
$40.00 CAD
$47.00
Best Savings

First Period Kit - Bikini

From 
$148.50 CAD
$198.00
Best Savings

Period Swim Full-Coverage Bikini Bottom

$55.00 CAD
Mix, Match & Save

Color: Black Limited Edition

+3

Period Swim Bikini Bottom

$55.00 CAD
Mix, Match & Save

Color: Black Limited Edition

+2
4.6
Rated 4.6 out of 5 stars
Based on 18 reviews
Write a Review (Opens in a new window)
18 reviews
  • Rated 5 out of 5 stars
    5 months ago
    Vert comfy

    My Daughter love it.

    Karine B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    6 months ago
    Great! But please improve the labels.

    Super comfy, enjoyable to wear. But Knix, for the love of all that is holy, PLEASE find a way to label each pair with their absorbency level. It is downright mean to expect my hormone overloaded, cramping body to wake up and remember which pair of underwear has the right absorbency equivalent for the day. You've gotten them all down to such nice, light, non-bulky formats that it isn't obvious to my period-foggy brain which is which, and I feel like that's a pretty easy fix on your end. So please, help a girl out.

    Carlee F.
    Was this helpful?
  • Rated 5 out of 5 stars
    10 months ago
    They are amazing

    Picked these up for my niece and she loved them!

    Nicole k.
    Was this helpful?
  • Rated 4 out of 5 stars
    10 months ago
    Game changer

    My daughter loves these. They fit well, are comfortable (even during sports) and wash well. Going back to order more.

    Erin C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    10 months ago
    Great product!

    My daughter loves this underwear and has no problem wearing them. Easy to wash and she says they are very comfortable :)

    jessica m.
    Was this helpful?
  • Rated 4 out of 5 stars
    11 months ago
    Underwear

    Love these boy short underware

    Bea B.
    Was this helpful?

Your questions, answered.