Skip to Content

The Best Period Underwear, Tested in Our Labs and by Real Users

Shop the most absorbent and affordable period panties for your flow.

By
Jump to Products
four pairs of period underwear on a blue set with flowers, good housekeeping's best period underwearpinterest
mike garten

We've been independently researching and testing products for over 120 years. If you buy through our links, we may earn a commission. Learn more about our review process.


Period underwear fits just like regular underwear but features a special absorbent gusset that helps prevent blood from leaking through. They're a sustainable and cost-effective alternative to disposable menstrual products like pads, tampons and liners. Because not everyone is sold on these ingenious products, the Good Housekeeping Institute Textiles Lab's fiber scientists tested period underwear in our Lab using cough syrup to mimic period flow and sent styles to consumer testers with a range of body shapes, flow levels and underwear style preferences to find the best buys.

While there are now plenty of stylish and comfortable options available, you'll want to steer clear of any styles that aren't absorbent enough or add unnecessary bulk. To find the best period underwear, the Good Housekeeping Institute Textiles Lab checked the absorbency of top-rated pairs using red cough syrup. (Manufacturers use it to test pads and tampons too!) We also sent 21 different styles to 100 testers to get feedback on comfort, leaks and more. We reviewed over 1,500 data points before making our recommendations.

If you're new to wearing period underwear, one word of caution: In our Lab tests, we found that even the most effective styles couldn't absorb the cough syrup as well as traditional pads. So if you have a heavy flow, you may want to wear period underwear as a backup to a menstrual cup or other disposable menstrual supplies rather than relying on it alone.

Keep reading to shop our top-performing picks and to find more information about period underwear materials, safety and sustainability at the end of this guide. Looking for more ways to improve your period experience? Check out our top picks for the best period swimwear and the best heating pads to soothe cramps.

1
Best Overall Period Underwear

Knix Leakproof Bikini

Best Seller
Leakproof Bikini
$22 at Knix
Credit: Knix
Pros
  • Nude color options
  • Breathable, lightweight materials
  • Top-performing absorbency without a bulky pad
Cons
  • Not designed for heavy flow days or overnight protection

Testers were impressed with this pair's breathable nylon/Lycra material that felt just like regular underwear with a cotton gusset and a barely-there feel. This style is available in five nude shades to match a variety of skin tones and fifteen other fun color and pattern options. We tested the lightest absorbency level, but this pair is now available in medium absorbency.

Lab results: This pair easily soaked up liquid at various angles and aced all of our Lab evaluations. They showed no signs of wear after we laundered them multiple times, and GH analysts appreciated the lightweight fabric similar to athletic wear that stays hidden under clothes — no more panty lines.

Tester notes: Testers were surprised by how thin the pad was, and one said that these are the "perfect backup to tampons on heavier flow days." They're also ideal for lighter days on their own. Another tester said they were "the most comfortable period underwear I've ever tried." Another especially liked that they were "soft and stretchy and not bulky."

AbsorbencyLightest (1 tampon's fluid) and Medium (3 tampons' fluid)
Sizing XS–XXXXL
Care instructionsMachine wash cold and lay flat to dry.
Body material77% nylon, 23% Lycra Xtra Life
Gusset material86% cotton, 10% spandex, 4% carbon with inner 100% polyester layer
Return policyFree returns within 30 days; can be worn and washed.
two pairs of knix leakproof bikini period underwear on a white table, good housekeeping's best period underwear testing
Emma Seymour
2
Best Value Period Underwear

Bambody Absorbent Panty Period Underwear

On Sale
Absorbent Panty Period Underwear
Credit: Bambody
Pros
  • Best seller on Amazon
  • Sold individually or in packs for a lower cost
  • Mesh detailing on the sides
Cons
  • Runs small, according to testers

Period panties can get expensive, but this pair is more affordable and a popular choice on Amazon. Plus, they have free two-day shipping for Prime members in case you need them quickly. There's a leakproof barrier that extends from the front all the way through the back.

Lab results: This pair washed beautifully with no shrinkage or changes in appearance after five wash cycles. The absorbent core proved to be decently absorbent, though when the pair was held at an angle, it showed more leaks than other tested styles. Just note that these claim to be made with "bamboo fabric," which is really rayon.

Tester notes: Calling them "hassle-free," testers liked wearing this period underwear instead of pads. One tester said, "These don't feel bulky and I didn't worry about leaking," while another noted, "The fabric was nice and smooth." Multiple testers reported that this pair ran small and opted to size up.

AbsorbencyHeavy (4 tampons' fluid)
Sizing4–10 (equivalent to XS–XXXL)
Care instructionsMachine wash and tumble dry low or air dry.
Body material95% Rayon, 5% Spandex
Gusset materialNot listed
Return policyDepends on color and size
Advertisement - Continue Reading Below
3
Most Popular Period Underwear

THINX Hiphugger

Hiphugger
Credit: THINX
Pros
  • Thousands of five-star online reviews
  • Original brand to develop the period underwear industry
  • Easily absorbed and held onto fluid in Lab evaluations
Cons
  • Some testers found them too tight and constrictive

Thinx is probably the most popular brand on this list, and that's for two good reasons: Its marketing campaigns are everywhere and our testers love the product. One user thought they would never find period panties that were stylish, comfortable and functional — until they tested out a pair of Thinx.

Lab results: We applied our test fluid at an angle, and the absorbent core quickly trapped it with only minimal runoff. The underwear showed no signs of wear after laundering, and the mesh detailing stayed in prime condition.

Tester notes: Multiple testers were especially impressed with this pair's impressive absorbency. One tester said this pair was "absorbent and didn't leak at all." Another tester reported, "They really stayed in place which gave me more confidence than another pair I tried." However, some testers noted that the band was a bit snug.

Take note: Thinx recently settled a class action lawsuit claiming its underwear contains man-made "forever chemicals" per- and polyfluoroalkyl substances (PFAS), though the brand denies these claims. Get more information on the settlement here.

AbsorbencyModerate (3 tampons' fluid) and Super (5 tampons' fluid)
SizingXS–4X
Care instructionsMachine wash cold and lay flat to dry.
Body material84% polyamide, 16% elastane
Gusset material95% cotton, 5% elastane with polyester and PU liner
Return policyThe brand offers a 45-day trial on all orders, saying "if you’re unhappy with your purchase, we’ll try to make it right."
a good housekeeping analyst holding up a red pair of thinx hiphugger period underwear in the textiles lab, good housekeeping's best period underwear
Philip Friedman
4
Best Size-Inclusive Period Underwear

TomboyX First Line Period Bikini

First Line Period Bikini
Pros
  • Excellent range of sizes
  • Absorbed all the fluid in our tests without leaking
  • Longer pad for full coverage
Cons
  • Bulkier fit, according to some testers

This style from TomboyX has the most inclusive size range out of all the styles we tested — from 3XS to 6XL. Our pros love that this brand features a variety of gender-inclusive options too.

Lab results: With a longer liner and wide waistband, this pair stayed in place securely and absorbed fluid quickly in our tests. GH analysts also note that the full coverage design would be great to use as overnight protection.

Tester notes: Made with a cotton/spandex blend, testers said the "fabric was super soft." One tester shared that it's "high wasted, comfortable and I felt confident with the protection it was providing." While testers did note this option was visible under some clothing items, they especially appreciated its high absorbency when worn at home or overnight.

AbsorbencyHeavy coverage (8 tsp fluid)
Sizing 3XS–6XL
Care instructionsMachine wash cold in a mesh bag, line dry overnight. Avoid machine drying.
Body material95% cotton, 5% spandex
Gusset material89% polyester, 11% spandex
Return policyFree returns for used first-time underwear orders from TomboyX; future orders can be returned unused and unwashed within 30 days.
Advertisement - Continue Reading Below
5
Best Period Underwear for Teens and Tweens

KT by Knix Super Leakproof No-Show Underwear Bikini

Super Leakproof No-Show Underwear Bikini
Credit: KT by Knix
Pros
  • Breathable material
  • 17 color options
  • Top tested brand
Cons
  • Some online reviewers found it challenging to find the right size

Your first period can be exciting but overwhelming too. KT by Knix provides comfy options that can make this new stage easier for tweens so they can worry less about leaks. Available in light and medium absorbencies too, this best-selling super absorbency bikini style offers ample coverage and is available in a variety of fun shades. The brand also offers a starter set with two pairs of underwear and sleep shorts. Because this pick features teen sizing (which is inconsistent from brand to brand), some online reviewers found it tougher to find the best size for them.

Lab results: The brand's original leakproof underwear aced Lab evaluations for quickly absorbing fluid at a variety of angles without leaking. The sleep shorts have a much larger pad for full coverage that also held onto an impressive amount of fluid in our test.

Tester notes: In our extensive testing of period underwear, Knix styles continue to be top performers. "They have held out on her heaviest days and she absolutely loves them," said one online reviewer about her 11-year-old daughter. "So grateful for this fantastic solution for my little one." Another online reviewer said her 13-year-old daughter "goes all day at school without anxiety and leaks. Phenomenal." She even added, "Where were these when I was in middle school and high school?"

AbsorbencyHeavy coverage (8 tampons' fluid)
SizingXXS-XXL (Teen sizing)
Care instructionsMachine wash cold and lay flat to dry or tumble dry low.
Body material70% Nylon, 30% Spandex
Gusset material100% Polyester, PU Film
Return policyYour first order has a 30-day return period for one worn product. Future underwear products cannot be returned.
a good housekeeping analyst holding up a black pair of kt by knix leakproof underwear with the black sleep shorts on the lab bench, good housekeeping's best period underwear
Philip Friedman
6
Softest Period Underwear

Aerie Real Period Boybrief Underwear

Real Period Boybrief Underwear
Pros
  • Affordable price
  • One of the few styles that's dryer safe
  • Super soft cotton-blend fabric
Cons
  • Some online reviewers note that the leg openers are tight

Starting at $20, this period underwear from Aerie feels similar to the brand's best-selling traditional underwear. This pick is available in seven style options, including bright shades, neutrals and stripes.

Lab results: Made with a cotton/polyester blend, Aerie's period undies had a soft feel and didn't shrink after machine washing. It absorbed fluid quickly and showed no run-off when fluid was applied at an angle.

Tester notes: Out of all the pairs we tested, GH analysts rated this one as the softest — and testers agreed too. One tester said, "They were very comfortable and provided good protection." Some online reviewers note that the leg holes are tight.

AbsorbencyModerate coverage (2 tampons' fluid)
SizingXS–XXL
Care instructionsPre-rinse by hand in cold water. Machine wash on delicate with cold water in a mesh laundry bag and tumble dry low.
Body material95% Cotton, 5% Elastane
Gusset materialNot listed
Return policyFree returns for unworn and unwashed products.
Advertisement - Continue Reading Below
a pair of blue aerie leakproof period underwear on a white table, good housekeeping's best period underwear testing
Emma Seymour
7
Best Period Underwear for Sleep

Thinx Sleep Shorts

Sleep Shorts
Credit: Thinx
Pros
  • The perfect shorts to wear if you're staying home with cramps
  • Cozy soft materials
  • Long, ultra absorbent liner for full coverage
Cons
  • Expensive

If you don't like the look of typical period underwear, you may love this overnight option. They look just like loose shorts from the outside, but this pick from Thinx has super-absorbent built-in period underwear for the ultimate loungewear option.

Lab results: This pick features a larger pad that absorbed fluid quickly and held onto it, showing no leaks during testing. It didn't shrink after laundering either — GH analysts also noted that the fabric stayed just as soft after multiple cycles.

Tester notes: Testers loved that they "offered excellent protection while looking like a typical pair of sleep shorts." Raving that the outer fabric is "super soft," multiple testers noted that the pad is on the bulky side and best for heavy flow days.

AbsorbencyFull coverage (5 tampons' fluid)
SizingXS–4X
Care instructionsMachine wash cold and then hang to dry.
Body material96% modal, 4% elastane
Gusset material100% polyester with PU liner
Return policyThe brand offers a 45-day trial on all orders, saying "if you’re unhappy with your purchase, we’ll try to make it right."
a good housekeeping's analyst holding up a pair of black thinx sleep shorts in the lab, good housekeeping's best period underwear
Philip Friedman
Advertisement - Continue Reading Below
8
Best Thong Period Underwear

Saalt Leakproof Seamless Thong

 Leakproof Seamless Thong
Credit: Saalt
Pros
  • Super discreet liner
  • Stretchy material
  • Silky smooth feel
Cons
  • Very light coverage

Featuring seamless construction with silky materials, Saalt's period underwear thongs look and feel just like everyday underwear. It's perfect to wear under leggings or other form-fitting clothing to avoid any panty lines.

Lab results: The discreet liner absorbed fluids well and held onto them to keep you dry. The liner is smaller than other styles, so it did show some leakage during our evaluations. This pair is best to be worn as backup protection or on very light days.

Tester notes: Testers especially loved the thinness of Saalt period underwear and agreed that they should be worn alongside other menstrual products. One tester said, "This thong feels like my favorite lingerie while giving me peace of mind during my period."

AbsorbencyLight (1 tampon's fluid)
SizingXS–2XL
Care instructionsMachine wash cold and hang dry
Body material62% polyamide, 38% Lycra Xtra Life elastane
Gusset material100% polyester
Return policyYour first order has a 30-day return period for one worn product. Future underwear products cannot be returned.
a good housekeeping analyst holding up a burgundy saalt leakproof thong in the textiles lab, good housekeeping's best period underwear
Philip Friedman
9
Best Period Underwear With Reusable Pads

Aisle Boxer Brief

Boxer Brief
Pros
  • Ultra absorbent core with optional reusable pad
  • Uses sustainable materials like Tencel and organic cotton
  • Can purchase the reusable pads separately
Cons
  • Not all testers liked using a removable pad with period underwear

Aisle period underwear works a bit differently than the other picks on this list. The underwear has a removable insert that absorbs your period (along with an absorbent liner) instead of the protection being built-in, so it's kind of like wearing a reusable pad with your underwear.

Lab results: The pad quickly absorbed fluid and held onto it, showing only minimal runoff leaks on the sides. GH analysts appreciated that this style is available in sizes XXS–5X.

Tester notes: Not all of our testers liked the concept, but they still found them "comfortable to wear" with a "soft feel." Multiple testers did note leaks.

AbsorbencySuper heavy coverage (8+ tampons' fluid with removable insert; 4 tampons' fluid without)
SizingXXS–5X
Care instructionsRinse out in cool water, then wash and dry with your regular laundry.
Body material48% TENCEL lyocell, 48% organic cotton, 4% spandex
Gusset material90% Truetex™ (88% recycled polyester, 12% organic cotton), 10% TPU
Return policyFirst time orders can be returned used within 60 days. Future orders can be returned unused and unwashed within the 60-day return window (these products are then donated).
Advertisement - Continue Reading Below

How we test period underwear

a good housekeeping analyst evaluating period underwear in the lab, good housekeeping's best period underwear
Philip Friedman

In the Lab, we evaluated absorbency speed, surface wetness, shrinkage and runoff to ensure that each product we recommend will perform. Then we sent each style home with consumer testers to evaluate comfort and style.

a pair of period underwear in the midst of testing with red cough syrup, good housekeeping's best period underwear
Emma Seymour

✔️ Absorbency speed: We used cough syrup to mimic the viscosity of menstrual flow just as manufacturers do to test pads and tampons. To measure absorbency speed, we applied cough syrup to the underwear with a syringe and timed how long it took for it all to completely absorb into the pad.

a person cutting a wooden toy
Philip Friedman
Advertisement - Continue Reading Below
a weight on top of filter papers on period underwear as part of our testing of the best period underwear, good housekeeping's best period underwear
Philip Friedman

✔️ Surface wetness: After the absorbency speed test, we placed filter paper on top and then added a 5-pound weight. We evaluated the filter paper to see how well the period underwear held onto the fluid (i.e., to see if the period underwear will keep you dry!). This test was completed when each pair was brand new then again after one and five washes.

a gh analyst putting red cough syrup on a pair of period underwear at a 45 degree angle as part of good housekeeping's best period underwear testing
Amanda Constantine

✔️ Wash and wearability: After a pair was washed twice, we evaluated runoff, which refers to how much fluid will roll off the underwear when it’s tilted to a 45-degree angle. Since no one just sits still when on their period, this test determines if the period underwear will be absorbent at different angles too. Our pros also evaluated shrinkage after one and five washes.

✔️ Comfort and fit: In addition to all our Lab evaluations, every pair was sent to five testers of different sizes and menstrual flows to receive feedback on leaks, comfort, fit, absorbency and more.

Headshot of Emma Seymour
Emma Seymour
Textiles, Paper & Apparel Lab Senior Analyst

Emma Seymour (she/her) is a senior product analyst at the Good Housekeeping Institute's Textiles, Paper and Apparel Lab, where she has led testing for luggage, pillows, towels, tampons and more since 2018. She graduated from Cornell University with a bachelor of science in fiber science and apparel design and a minor in gerontology, completing research in the Body Scanner Lab on optimizing activewear for athletic performance. 

Watch Next
 
preview for Featured Videos From Good Housekeeping US
Advertisement - Continue Reading Below

Product Reviews

best robot vacuums, according to cleaning experts

The Best Robot Vacuums

a variety of nonstick pots and pans

The Best Nonstick Cookware

10 best vacuums on amazon, according to cleaning experts

The Best Vacuums on Amazon

waterpiks being tested

The Best Water Flossers of 2024

Advertisement - Continue Reading Below
Advertisement - Continue Reading Below