Shop Leakproof Underwear

★★★★★ 100,000+ 5-STAR REVIEWS

Really, it’s just better underwear

For blood, sweat, pee, and discharge. Leakproof means you’re good.

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# 1 Leakproof Brand in North America

20M+ pairs sold

100,000+ 5-Star Reviews

Est. 2013

Leakproof Absorbency Guide

Good for

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

Absorbs

About 7-11 super tampons or 1.5-2.5 super pads

Good for

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

Absorbs

About 4-7 super tampons or 1.5-3 regular pads

Good for

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

Absorbs

About 2-4 super tampons or 1-1.5 regular pads

Good for

Daily freshness. For sweat, discharge, period spotting, or backup protection.

Absorbs

About 1-3 regular tampons or 1-3 pantyliners

Good for

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

Absorbs

Zero absorbency

Built-in patented <em>protection</em> that feels like nothing at all

Built-in patented protection that feels like nothing at all

How Leakproof keeps you dry, fresh, and in control:

Soft Top Layer

Wicks away moisture from your skin and fights odor.

Middle Layer

Quickly soaks up the liquid that’s moved down from the top layer.

Leakproof Layer

Seals in liquid discreetly, so leaks can’t reach your clothes or sheets.

360 LeakSeal™ Edges

Our patented tech locks in leaks at every edge.

“The best. I love the seamlessness, the fit. I never have to worry about leaks.”

Cynthia H. Light Leakproof UltraThin No-Show Bikini

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“Literally the best thing that ever happened to me was discovering these.”

Elise C. Super Leakproof® Dream Short

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“This was my first time trying period underwear and I'm hooked.”

Lex G. Leakproof UltraThin No-Show Bikini

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Not sure which absorbency is right for you?

Take the quiz & get 15% off*

How to wash

Knix underwear is 100% reusable and machine washable, just like your regular undies.

Rinse

Not required. But for best results, you can rinse your leakproof with cold water in the tub or sink before washing.

Wash

Machine wash on a cold, gentle cycle with mild detergent.

Dry

For their longest life, air drying is best. Hang or lay flat to dry.

Avoid

Fabric softeners, bleach, ironing, or heat from the dryer.

Not just underwear

Your questions, answered.

Mix, Match & Save - Terms & Conditions

*Offer valid on select underwear styles on knix.com and knix.ca, while supplies last. When you purchase three or more eligible styles from the same category, you’ll receive the corresponding offer:

- Light & Essential: 3 for $60
- Moderate & Heavy: 3 for $75
- Ultra: 3 for $99

Exclusions: Super Leakproof Dream Short, Super Leakproof Dream Boxer, Leakproof CoreLove High Rise, Leakproof Modal Rib Boxer Brief, Luxe Modal Leakproof Sleep Boxer, Leakproof Cotton Modal Bikini, Leakproof Cotton Modal High Rise, all Thigh Saver styles and Last Call items.

Discount is automatically applied at checkout and is based on eligible items in your order. No rain checks or price adjustments on previous purchases.

What is Leakproof technology and how does it work?

Are Leakproof products tax-free?

*Period underwear and pads are exempt from federal sales tax in Canada. They are also exempt from most provincial / harmonized sales taxes. But are subject to the following provincial sales tax rates which will apply to orders shipped to the following provinces and to orders purchased in retail stores located in the following provinces: British Columbia and Manitoba: 7% PST; Saskatchewan: 6% PST.

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