The Best Period Underwear of 2026, Tested in Our Labs and by Real Users
Shop the most absorbent and affordable period panties for your flow.
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.
When I first learned about period underwear, I was skeptical—underwear that absorbs your period flow sounded uncomfortable and also unsanitary. But, after testing period underwear both personally and in the Good Housekeeping Institute Textiles Lab, I am sold on the concept. 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.
Our top picks:
- Best Overall: Knix Leakproof UltraThin No-Show Bikini
- Best Value: Bambody Absorbent Panty Period Underwear
- Best for Sleep: THINX Ultra Soft Sleep Shorts
- Best Size-Inclusive: TomboyX First Line Period Bikini
- Best Thong: Saalt Leakproof Seamless Thong
- Best With Reusable Pads: Aisle Boost Boxer
I have tested over 25 different pairs in the Textiles Lab and sent many to consumer testers over the past seven years, receiving feedback on comfort, leaks, and more. I even tried most of these pairs myself. In the Lab, I evaluated each pair's absorbency using red cough syrup to mimic period flow's viscosity (manufacturers use it to test pads and tampons too!). In recent years, there has been concern around period underwear containing PFAS (also known as "forever chemicals"). I spoke with Alissa Cordner, Ph.D., co-director of the PFAS Project Lab based at Northeastern University, to discuss the safety of period underwear.
When we tested period underwear, many testers didn't realize that these products are often covered by your Flexible Spending Account (FSA), Health Savings Account (HSA) or Health Reimbursement Account (HRA) benefits. Purchasing period underwear is a great way to utilize these benefits.
Pros
- Breathable, lightweight materials
- Top-performing absorbency without a bulky pad
- Thin fabric helps mitigate panty lines
Cons
- Make sure to follow laundering instructions closely to prevent fraying
Our consumer 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 a range of absorbencies from Light to Ultra.
How it performed in our tests:
✔️ This pair easily soaked up liquid at various angles and aced all of our Lab evaluations. These period panties showed no signs of wear after we laundered them multiple times. However, it's important to closely follow laundering instructions to prevent the underwear from fraying.
✔️The lightweight material stayed hidden under clothes. GH analysts liked that the fabric was similar to athletic wear for a breathable feel without panty lines. One tester echoed similar sentiments calling them "soft and stretchy and not bulky."
✔️ 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."
Features at a Glance
| Absorbency | Light (1–3 tampons), Moderate (2–4 tampons), Heavy (4–7 tampons), and Ultra (7–11 tampons) |
| Body material | 77% nylon, 23% Lycra spandex |
| Gusset material | 86% cotton, 10% spandex, 4% carbon |
| Care instructions | Machine wash cold and lay flat to dry. |
| Return policy | Eligible for exchange or store credit within 30 days of delivery. The item may be used. |
| Sizing | XS–XXXXL |
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 than most and a popular choice on Amazon. Plus, they have free two-day shipping for Prime members in case you need them quickly, free returns within 30 days, and are sold individually or in multipacks of three or six for a lower cost. There's a leakproof barrier that extends from the front all the way through the back, plus it has stylish mesh detailing on the sides.
How it performed in our tests:
✔️ This pair washed beautifully with no shrinkage or changes in appearance after five wash cycles. Just note that these claim to be made with "bamboo fabric," which is really rayon.
✔️ It leaked a bit in Lab tests. 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.
✔️ Testers liked wearing this period underwear instead of pads, with one calling them "hassle-free." A different consumer tester said, "These don't feel bulky and I didn't worry about leaking," while another noted, "The fabric was nice and smooth."
✔️ It may benefit to size up. Multiple testers reported that this pair ran small and opted to size up.
| Absorbency | Heavy (4 tampons' fluid) |
| Body material | 95% rayon, 5% spandex |
| Gusset material | Not listed |
| Care instructions | Machine wash and tumble dry low or air dry. |
| Return policy | Depends on color and size |
| Sizing | XXS–3X |
Pros
- Super soft, cozy material
- Look like PJ shorts with a hidden, built-in liner
- Highly absorbent core
Cons
- Because it's designed for overnight protection, pad is a bit bulky
If you don't like the look of typical period underwear, you may love this overnight option. It looks just like loose shorts from the outside, but this pick from Thinx has super-absorbent built-in period underwear for the ultimate loungewear.
How it performed in our tests:
✔️ Testers liked that they fit like traditional sleep shorts with top-notch protection. One tester said her favorite thing about the shorts was that they "offered excellent protection while looking like a typical pair of sleep shorts."
✔️ This pair stayed leak-free in Lab tests. The shorts feature a larger pad that absorbed fluid quickly and held onto it, showing no leaks during testing.
✔️ The fabric held up to multiple wash and dry cycles. The pair didn't shrink after laundering either—GH analysts also noted that the fabric stayed just as soft after multiple cycles.
✔️ The pad is a bit bulky and best suited for heavy flow days.
| Absorbency | Full coverage (5 tampons' fluid) |
| Body material | 96% modal, 4% elastane |
| Gusset material | 100% polyester with PU liner |
| Care instructions | Machine wash cold and then hang to dry. |
| Return policy | The brand offers a 45-day trial on all orders, saying "if you’re unhappy with your purchase, we’ll try to make it right." |
| Sizing | XS–4X |
Pros
- Excellent range of sizes
- Absorbed all the fluid in our tests without leaking
- Long 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.
How it performed in our tests:
✔️ The long liner absorbed fluid quickly in Lab tests. The wide waistband also helped this pair stay in place.
✔️ Testers liked its soft, smooth feel. Made with a cotton/spandex blend, several testers said the "fabric was super soft." One tester shared that it's "high wasted [and] comfortable and I felt confident with the protection it was providing."
✔️ The full coverage design is well suited for overnight protection. While some testers noted this option was bulky and visible under some clothing items, they especially appreciated its high absorbency when worn at home or overnight.
| Absorbency | Heavy coverage (8 tsp. fluid) |
| Body material | 95% cotton, 5% spandex |
| Gusset material | 89% polyester, 11% spandex |
| Care instructions | Machine wash cold in a mesh bag, line dry overnight. Avoid machine drying. |
| Return policy | Free returns for used first-time underwear orders from TomboyX; future orders can be returned unused and unwashed within 30 days. |
| Sizing | 3XS–6XL |
Pros
- Super discreet liner
- Stretchy material
- Silky smooth feel
Cons
- Very light coverage
Featuring seamless construction with silky, stretchy materials, Saalt's period 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.
How it performed in our tests:
✔️ The discreet liner absorbed fluids well and held onto them to keep you dry. The liner is smaller than other underwear styles, so it did show some leakage during our evaluations.
✔️ The thong design stays perfectly hidden. One consumer tester said, "This thong feels like my favorite lingerie while giving me peace of mind during my period."
✔️ This pair is best to be worn as backup protection or on very light days. Testers especially loved the thinness of Saalt period underwear and agreed that they should be worn alongside other menstrual products.
| Absorbency | Light (1 tampon's fluid) |
| Body material | 62% polyamide, 38% Lycra Xtra Life elastane |
| Gusset material | 100% polyester |
| Care instructions | Machine wash cold and hang dry. |
| Return policy | Your first order has a 30-day return period for one worn product. Future underwear products cannot be returned. |
| Sizing | XS–4XL |
Pros
- Ultra-absorbent core with optional reusable pad
- Uses sustainable materials like Tencel and organic cotton
- Comfy boxer design
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 period underwear has a thin built-in liner for light absorbency, but you can add the included removable insert on heavier days. (Extra removable pads are sold separately.) It feels more similar to wearing a pad with your underwear. The comfy boxer design is made using sustainable materials like Tencel and organic cotton.
How it performed in our tests:
✔️The underwear liner and the insert 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.
✔️ Not all of our testers liked the concept of removable pads. They still found them comfortable to wear with several noting they had a "soft feel." Multiple testers did note leaks.
| Absorbency | Super heavy coverage (8+ tampons' fluid with removable insert; 4 tampons' fluid without) |
| Body material | 48% Tencel lyocell, 48% organic cotton, 4% spandex |
| Gusset material | 90% Truetex (88% recycled polyester, 12% organic cotton), 10% TPU |
| Care instructions | Rinse out in cool water, then wash and dry with your regular laundry. |
| Return policy | First 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). |
| Sizing | XXS–5X |
How we test period underwear
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. I have been testing period underwear for the past seven years at the Good Housekeeping Institute Textiles Lab, developing these standards alongside expertise from industry leaders:
✔️ 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.
✔️ 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.
✔️ 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.
What to look for when shopping for the best period underwear
With more and more period underwear styles available on the market, finding the right pair can be challenging. GH textile pros found the key features to look for when shopping:
✔️ Absorbency: Period underwear is available in different absorbencies. Some styles are meant to be worn without any other period products while others are intended as back-up protection. We recommend having styles with a few different absorbencies to suit different days of your period.
✔️ Styles: Just like regular underwear, period panties are available in different cuts like high-waisted, bikini, hipster, and thongs. Opt for period underwear styles similar to the styles you normally like to wear.
✔️ Use: Period panties are designed to absorb menstrual flow, so most styles aren't well suited for incontinence. Look for styles that suit your needs. If you're new to period underwear, try an overnight style for nighttime protection—this was a favorite among our testers.
✔️ Fit: Period underwear must fit properly to prevent leaks while feeling comfy all day. Some testers found that period underwear can run small to ensure a snug fit. Several testers who were between sizes opted to go up a size for a more comfortable fit, but most went with their usual size in underwear.
How does period underwear work?
Designed to look and fit just like your everyday underwear, period underwear has an added absorbent gusset that holds onto menstrual flow to keep you dry and comfortable. The absorbent core features multiple layers of fabric for varying levels of absorbency depending on the brand and style. Pads and tampons are disposable products, but period underwear can be washed and re-worn, making it a more sustainable purchase over time.
How to use period underwear
You can wear period underwear on its own or as a backup with other menstrual products like a tampon or a menstrual cup. It has become an increasingly popular option among teens and tweens because period underwear is less bulky compared to traditional pads.
I recommend using bikini or hipster style period underwear (like Knix Leakproof Bikini) for everyday wear during your period. A sleep style like the Thinx Ultra Soft Sleep Short is a great introduction to period underwear. Thong styles absorb less flow and are best suited as back-up protection or on lighter days.
The Best Period Swimwear
Cramps But No Period? Here's What Might Be Up
The Best Menstrual Cups
Paid Time Off Should Include Period Time Off
![jennifer garner at peacocks the five star weekend premiere held at the hammer museum on july 08, 2026 in los angeles, california photo by christopher polkdeadline via getty images](https://hips.hearstapps.com/hmg-prod/images/e417e56d-f9fc-4b35-9e34-5853ed84cf23.jpeg?crop=0.666727075027xw:1xh;center,top&resize=360:* "Peacock's "The Five Star Weekend" Premiere")
