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All Underwear
From ultra-soft fabrics and seamless styles to super absorbent underwear, you’re covered 24/7/365.
HeavyUltraZeroTeen Underwear
Lightest Absorbency
Lightest periods, spotting, sweat & discharge - absorbs about 0.5-1 regular tampon worth.
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13
+
19
+
11
+
1
+
18
Light Absorbency
Light periods, backup protection & sweat - absorbs about 1-3 regular tampons’ worth.
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16
+
7
+
6
Medium Absorbency
Medium periods, light bladder leaks & sweat - absorbs about 2-3 super tampons’ worth.
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8
+
7
+
12
+
7
+
1
+
1
Period protection
down to a science
Learn MoreTikTok
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1
Heavy Absorbency
Heavy periods, overnight protection & light bladder leaks - absorbs about 3-6 super tampons’ worth.
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7
+
11
+
6
+
4
+
3
Ultra Absorbency 💧💧💧💧
Extra heavy periods, overnight protection & light bladder leaks - absorbs about 7-9 super tampons’ worth.
Zero Absorbency
Everyday wear with no leakproof protection - zero absorbency.
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4
+
10
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2
+
3
+
2
Teen Period Underwear
Moisture-wicking, odor-crushing, life-changing leakproof undies.
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1
+
8
+
7
+
8
+
2
+
3
+
2
+
2
+
1
+
1
+
1
From ultra-soft fabrics and seamless styles to super absorbent underwear, you’re covered 24/7/365.
Shop by Silhouette
Your leakproof questions, answered.
Items purchased on sale between August 28, 2024-September 2, 2024 are exchange only.
What size am I? Great question! Check out our size guide to determine your best fit or book a Virtual Fitting.
Is Essential underwear leakproof? No. Our Essential Underwear does NOT contain our Leakproof technology and does not protect against leaks. That being said, our Essential Underwear is comfortable, practical and great for everyday wear.
Online Ordering
When I add an item to my cart, is it put on hold for me?
No, items are not reserved for you until your payment is processed and your confirmation number is received. We recommend shopping early (and having your sizing ready) in order to avoid disappointment.
What payment method options are available?
You’re able to use a variety of payments, including credit card, Knix gift cards, PayPal, AfterPay (USA), Sezzle (CAN) and accelerated checkout options.
Other Ordering Questions
Can I collect rewards points on my sale purchase?
Yes, purchases on knix.com and knix.ca are eligible to earn loyalty points.
Can I pay for my purchase using a Knix gift card?
Yes, you will be able to apply a Knix gift card towards your sale purchase.
Can I change or cancel my order?
Once an order is placed, we cannot guarantee any address or order changes. If you would like to change your order, please use the “chat” feature on our website or email info@knix.com as soon as possible.
knix.ca: Standard shipping is free on eligible orders over $100CAD*. Orders under $100CAD* are $12CAD for standard shipping. Orders delivering to NWT, Nunavut, and Yukon under $100CAD* are $20CAD for standard Canada shipping.
Free expedited shipping $150+
*After discounts, before shipping and taxes. Digital gift cards do not count towards the free shipping threshold.
knix.com: Standard shipping is free on eligible orders over $100USD*. Orders under $100USD* are $10USD for standard shipping. 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.
Free expedited shipping $100+*
*After discounts, before shipping and taxes
How long will it take before my order is shipped? Due to a high volume of orders, it can take up to 4 business days for your items to be processed and shipped.
Ultra
Extra heavy periods, overnight protection & light bladder leaks - absorbs about 13-17 tsp or 65-85 mL which is the equivalent of 7-9 super tampons’ worth.
Heavy
Heavy periods, overnight protection & light bladder leaks - absorbs about 6-11 tsp, 30-55 mL or the equivalent of 3-6 super tampons’ worth.
Medium
Medium periods, light bladder leaks & sweat - absorbs about 3-6 tsp, 15 -30 mL or the equivalent of 2-3 super tampons’ worth.
Light
Light periods, backup protection & sweat - absorbs about 1.5-3 tsp, 7.5-15 mL or the equivalent of 1-3 regular tampons’ worth.
Lightest
Lightest periods, spotting, sweat & discharge - absorbs about 1-1.5 tsp, 4-7.5 mL or the equivalent of 0.5-1 regular tampon worth.
Zero
Everyday wear with no leakproof protection - zero absorbency.
More ways to feel unapologetically free
Find an amazing wireless bra to match your Undies. Plus explore our other products, all designed to make you feel so comfortable in your own skin.
Period UnderwearBRASEVERYDAY UNDERWEAR SLEEPWEAR ACTIVEWEARAPPARELShapewearMaternity