
No more worrying about leaks. Period protection designed just for teens.
Periods shouldn’t come with this much stress
Periods are a top 5 anxiety-driver for teens. From school to overnight to just getting through the day, they worry about leaks a lot.
Kt period solutions can help them stop:
• Leaking overnight
• Leaking through clothes and sheets
• Constantly checking “just in case”
• Wearing backups
• Suffering through bulky pads and painful tampons
Period underwear, swim, and active look just like regular clothing, but they absorb leaks, protect against accidents, and help teens move through their day with confidence. So your teen can focus on being a teen.
Why leakproof?
Soft top layer
Middle absorbent layer
Bottom leakblocker layer
How to wash
Leakproof Absorbency Guide
Good for
Our longest front-to-back liner, designed for their heaviest flow days and overnight protection.
Absorbs
About 7-11 super tampons or 1.5-2.5 super pads
Good for
Perfect for overnight protection or your teens heaviest days when changing into a fresh pair might not be convenient.
Absorbs
About 4-7 super tampons or 1.5-3 regular pads
Good for
Designed for moderate flow days and everyday comfort.
Absorbs
About 2-4 super tampons or regular pads
Good for
Light protection for daily wear and confidence.
Absorbs
About light flow protection.
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.
Totally Not TMI
Kt Period
Playbook
There’s zero shame in teens wanting confidence,
not confusion when it comes to periods.
That’s why we made this free guide and workbook
just for them.
Best Sellers
Shop All

Period Swim Sport One-Piece

Super Leakproof® Sleepover Boxer

First Period Kit - Bikini

Light Leakproof Cotton Bikini Underwear

Full Coverage Leakproof Dance Underwear

Light Leakproof No-Show Bikini 3-Pack

Racerback Tankini + Swim Short Set

Super Leakproof® No-Show Bikini

Period Swim Full-Coverage Bikini Bottom

Super Leakproof® Sleepover Short

Super Leakproof® No-Show Bikini 3-Pack

Double Scoop + Full Coverage Swim Set

Period Swim Short

Period Emergency Kit - Bikini

Leakproof Starter Kit - Bikini

Leakproof UltraThin No-Show Bikini 3-Pack

Period Emergency Kit - Boyshort

Period Swim Bikini Bottom

Super Leakproof® Mini Sleepover Boxer

Leakproof UltraThin No-Show Bikini

Leakproof Cotton Underwear Bikini 3-Pack
Don't let periods stop swim days
1 in 2 teens miss out on swimming because of their period, but not with Period Swim.
Shop Period SwimYour questions, answered.
It's easy, we promise. Give them a quick rinse under cold water first, then toss them in the washing machine with your regular clothes, cold water, mild detergent, no softener or bleach. For drying: lay flat for medium absorbency styles, or tumble dry on low for high and super absorbency ones. That's it. No ironing needed!
Good news, period underwear and pads are exempt from federal sales tax in Canada, and most provincial/harmonized sales taxes too.
Each pair has a built-in liner that absorbs period blood, no pad or tampon required (unless you want one!). Period underwear comes in different absorbency levels so you can find what works best for your flow.
Ultra: Absorbs the equivalent of 7-11 super tampons. Our longest front-to-back liner, designed for heavy flow days and overnight protection.
Heavy: Absorbs the equivalent of 4–7 super tampons. Great for overnight or heavier days.
Moderate: Absorbs about 2.5 super tampons' worth. A solid go-to for medium flow days.
Light: Absorbs about 1 regular tampon's worth. Perfect for spotting, lightest days, discharge, and sweat.
Totally up to them! Every flow is different, and there's no wrong answer. Depending on the absorbency level and how heavy their period is, they can wear period underwear on their own or use them as backup.
Because they’re underwear, we can’t accept exchanges or returns on used items.
Save 15% on the Period Emergency Kit
School is stressful enough without leaks! Make sure teens are prepared for periods with the Period Emergency Kit. Underwear absorb up to 2.5 tampons worth of blood and fit discreetly in any backpack so they can change quickly and avoid any embarrassing leaks. Perfect for teens and tweens starting their first period or managing unpredictable cycles. Comfortable, washable, and parent approved for stress free school days.
Perfect Choice
Insanely comfortable. I wore it an entire day and felt completely dry despite it being a heavy day. Also surprisingly discreet, little to no lines.
Cute and Effective
They work just as well as the regular sized boxers! Very cute.
Cute, Comfortable, Competent
I’m not a fan of the Knix’s Women styles so I picked the Teen line instead and it still works. These are great for sleeping in and even in the morning when my period is at its heaviest.
Read More