Anyone who's ever gotten a period can probably relate to the inconveniences of menstruation. Its unexpected arrival without a tampon on hand? Yep. Shocked by the price of pads? Uh-huh. Favorite underwear ruined due to leaking? You betcha. There's no shortage of reasons to complain about a menstrual cycle, but what if we told you there's a solution to the madness?
Recent findings suggest that several period underwear products could contain PFAS, also known as "forever chemicals." Thinx in particular recently settled a lawsuit (Dickens, et al. v. Thinx Inc. Settlement) regarding the presence of PFAS in several of their styles, found by an independently conducted test. The suit argues that the presence of these chemicals is harmful to users and is contrary to brand’s advertising as free of harmful chemicals.
We've been continuing to research this topic and speak to medical professionals about potential risks, and you can learn more about it in our FAQ section.
Period underwear is exactly what it sounds like: panties worn during your period. They're absorbent like a pad, typically leak-proof, offer odor control, and allow you to forgo not only buying feminine hygiene products but also adding them to a landfill. When period underwear came to market less than a decade ago, it wasn't long before brands and consumers caught on to the life-changing invention.
According to Kiarra King MD, a board-certified OB/GYN in Chicago, they're absolutely a suitable alternative to pads and tampons. "Women and girls should feel comfortable and secure in whatever period product they choose," she tells Byrdie.
"On light days, period underwear can be used alone. You can shop by style and absorbency (light, moderate, heavy)," says Dr. Carolyn Moyers, DO, FACOG, a board-certified OB/GYN based in Fort Worth, Texas.
So if you’re interested in trying out period underwear, we put tons to the test and rounded up the best options for light days, heavy flows, and everything in between.
Keep reading to find the best period underwear tested by Byrdie.
Thinx For All Super Absorbency Brief
Could be just the slightest bit more absorbent
Though we loved many of the options we tested, this one is our favorite. The classic bikini style is comfortable and well-fitting, the fabric is soft, it has great absorbency, and it’s affordable and accessible. Our tester noted that the gusset is pretty thick, which is great for additional coverage and leak protection, and she also shared that the underwear has a soft, cotton feel. She was able to add five teaspoons of liquid that was absorbed quickly and produced just a bit of leaking after sitting for a moment. While there was a tiny bit of leaking, we think this underwear still lives up to its claim of being super absorbent. We also appreciate the brand's commitment to size inclusivity.
Price at time of publish: $17
Material: 95% cotton, 5% elastane | Absorbency: Super | Size Range: XS to 4X | Care Instructions: Machine wash cold, hang dry
AerieREAL Period Underwear
Long, thick gusset
A bit bulky
If you’re new to period underwear, it’s wise to start with a budget-friendly option until you’re sure that it’s a method of period care you like. In addition to being affordable, this option for light to medium flow days is great because it holds up to two tampons worth of liquid. Our tester shared that it absorbed liquid quickly, though it did leave a bit of wetness on the surface of the fabric.
The design features a stretchy waistband and a thick gusset that runs nearly all the way to the back of the underwear for added leak protection. While the length and thickness of the gusset are great for protection, it does add a bit of bulkiness to the underwear.
Price at time of publish: $10
Material: 50% cotton, 30% acrylic, 16% polyester, 4% elastane | Absorbency: Medium | Size Range: XXS to XXL | Care Instructions: Machine wash cold, tumble dry low
Proof Leak Proof High Waisted Lace Brief
Absorbs liquid quickly
Has pretty lace detailing
Waistband could be slightly more stretchy
It’s true, not all period underwear is aesthetically pleasing. But this design is both functional and pretty. It has moderate absorbency, meaning it will hold about three tampons’ worth of liquid, and our tester appreciated how quickly it absorbed liquid. She also noted that the outside of the underwear was completely dry after the absorbency test.
The fabric is soft, and the lace detailing adds a little something special to the design, but we wish the waistband were just a bit stretchier to allow for even more comfort.
Price at time of publish: $49
Material: Nylon, cotton, polyester, spandex, acrylate | Absorbency: Moderate | Size Range: XS to XL | Care Instructions: Machine wash cold, hang or lay flat to dry
Best for Light Flow
Thinx Air Hiphugger Period Underwear
Long gusset for extra protection
Thick, breathable fabric
Liquid takes a moment to absorb
This is the underwear we recommend most for very light days when your period is just beginning or nearing its end. The mesh fabric is soft and lightweight, making it very breathable and comfortable. It also features a long gusset that extends far back for added protection.
As for absorbency, it does hold two tampons’ worth of liquid without leaking, but it takes a minute for the liquid to fully absorb into the fabric. This is also a great option for you if you use other period care methods such as tampons or a menstrual cup, but you’re prone to leaking—it can provide an additional layer of protection.
Price at time of publish: $35
Material: 78% nylon, 22% elastane | Absorbency: Light | Size Range: XS to 4X | Care Instructions: Machine wash cold, hang dry
Best for Heavy Flow
Goat Union Overnight Period Underwear
Absorbs a large amount of liquid
Design features many seams which can be slightly uncomfortable
If you’re on the hunt for period underwear that will keep you protected on heavy-flow days, we recommend this one. While liquid does take some time to fully absorb, our tester was impressed with how much liquid this pair could absorb without leaking.
Note that while the fabrics are soft, the design does feature multiple seams, which can be a point of discomfort for some people. However, given the impressive absorption capabilities and affordable price tag, this underwear has our stamp of approval.
Price at time of publish: $17
Material: Cotton, spandex, nylon, polyester, bamboo cellulose | Absorbency: Super | Size Range: XS to 4XL | Care Instructions: Machine wash, hang dry
Thinx Period Pajama Sleep Shorts
Soft, comfortable material
Underwear part feels a bit bulky
Whether period underwear is your primary form of period care, or you just don’t like the idea of using other methods while you sleep, we highly recommend checking this pair out for nighttime. Our tester found that a large amount of liquid absorbed into the fabric quickly and did not leak. She also praised the design, saying that the fabric is soft and the long, fairly thick gusset is excellent for maximum leak protection. The one downside? While the attached underwear inside of the shorts provide great protection, they are slightly bulky.
Price at time of publish: $50
Material: Spandex, micro modal, cotton, polyester | Absorbency: Super | Size Range: XXS to 4X | Care Instructions: Machine wash cold, hang dry
Best for Exercise
Thinx Cycle Shorts
Material is stretchy but compressive enough to workout in
Wouldn’t be sufficient for heavy days
Finding great period underwear that looks and feels light underneath workout clothes can be tricky, which is why we love these cycle shorts that are designed with built-in period underwear. The shorts themselves are made out of a soft fabric that has the perfect balance of stretch and compression for a workout, and the underwear portion has a gusset that can hold up to two tampons worth of liquid. Our tester shared that while the underwear absorbed liquid during the absorption test, there was slight leaking. Considering that this design only claims to have light absorbency and doesn’t fully protect against leaks, we recommend wearing it on your lightest days or on heavy days in combination with another method.
Price at time of publish: $38
Material: Polyester, polyamide, elastane, cotton | Absorbency: Light | Size Range: XS to 4X | Care Instructions: Machine wash, line dry
Hamilton Beach Toastation Oven With 2-Slice Toaster Combo
Only functional for light days
Not all period underwear is bulky—take this pair, for example. While the design is only sufficient for light days (which the brand claims), it’s hard to believe that thong underwear this soft and seamless has any true leak protection at all—but it does. Our tester shared that it absorbed one teaspoon of liquid quickly and without leaking. It also comes in a wide range of sizes and colors, which is an added bonus. If we could change one thing about it, we wish it provided stronger leak protection for heavier flow days because it’s truly a great option for those that want to wear period underwear in a thong style.
Price at time of publish: $20
Material: Nylon, lycra, cotton, spandex, carbon | Absorbency: Light | Size Range: XS to 4XL | Care Instructions: Machine wash cold, tumble dry low
Dear Kate Ada Full Brief
Excellent absorption capability
Slightly pricey for underwear
Not all period underwear designs are super sexy, but you can find underwear that is both functional during your period and pretty too. This underwear features a lace waistband that gives it a sexy flare, as well as incredible absorption capability (despite the brand only claiming medium absorbency).
Our tester shared that the underwear successfully absorbed three tampons full of liquid without leaking, so she decided to add more liquid to test the limits. To her surprise, the fabric absorbed five tampons worth of liquid quickly and without spillage. While it is pretty pricey for one pair of underwear, the functionality and cute design make it a worthwhile investment if you’ve been searching for lingerie-like period underwear.
Price at time of publish: $46
Material: Nylon, elastane, polyester, lycra | Absorbency: Medium | Size Range: XS to 3X | Care Instructions: Machine wash cold, line dry
Rael Reusable Period Underwear
Soft, cotton fabric
Absorbs liquid quickly
Gusset could be slightly thicker for added protection
Limited size range
Whether it’s for comfort or sustainability reasons, many people seek out cotton clothing. If that sounds like you, you’ll appreciate that this underwear is made of 95 percent cotton. The material is comfortable, the design is simple and effective, and the absorbance capability is solid.
Our tester said that the fabric easily absorbed three tampons worth of liquid, but she noted that the gusset felt pretty thin, which made her nervous about its durability. It’s a great option for anyone looking for cotton period underwear, but we would like to see the brand extend the size range.
Price at time of publish: $20
Material: 95% cotton, rayon, spandex, polyester | Absorbency: Medium | Size Range: S to XL | Care Instructions: Pre-rinse, machine wash cold. Line dry or lay flat
Best High Waisted
Saalt Leakproof High Waist Period Underwear
Soft, luxurious-feeling fabric
Absorbency could be stronger
It seems like most period underwear options on the market are mid-rise, making really great high rise options hard to come by. But for those looking for a high-rise design, we recommend this one. Aside from the cool design, which features asymmetrical, lacey-looking mesh, the high-waisted nature of this underwear provides subtle tummy control too.
In terms of the fabric, our tester said it has a “soft, kind of luxurious-feeling.” However, in terms of absorbency, she noted that three tampons worth of liquid did leak. So, we recommend this underwear for light days, and if you’re going to wear it on heavy days, you might want to consider using additional period leak protection.
Price at time of publish: $39
Material: post-consumer recycled water bottles | Absorbency: Light | Size Range: XS to 2XL | Care Instructions: Rinse, machine wash cold. Hang dry
Best for Comfort
Cora Period Underwear
Absorbs liquid quickly
Soft, elastic waistband
Gusset could be slightly longer for added protection
If there’s one thing that everyone who menstruates has in common, it’s likely the desire to be comfortable. Tight or uncomfortable clothing is an absolute no-no during that time of the month. If you’re sensitive to restrictive clothing or lots of seams, this is the period underwear for you. It’s made from soft cotton, has a soft, elastic waistband, and absorbs liquid quickly. Our tester explained that the gusset remained dry to the touch once the liquid was absorbed, although she noted that it could be slightly longer in the back for added leak protection.
Price at time of publish: $25
Material: 100% cotton | Absorbency: Medium | Size Range: XS to 2XL | Care Instructions: Hand wash
Best Plus Size
TomboyX First Line Leakproof Bikini
Very inclusive size range
Thick, elastic waistband
Absorbency could be slightly better
Size inclusivity in the fashion industry still needs some improvement, but we’ll give credit where it’s due, and TomboyX did an awesome job with the size range of this underwear. It ranges from 3XS to 6X, meaning that a very large variety of people will be able to find their right fit. As for the design itself, the bikini shape is standard, the fabric is soft and comfortable, and the thick, elastic waistband is great for functionality purposes.
We will say, the absorbency that’s advertised for this underwear is a bit confusing. The brand says it provides light absorbency but should hold up to eight teaspoons of liquid, which would equate to pretty high absorbency if you ask us. In reality, our tester found that it was able to hold roughly five teaspoons of liquid comfortably—we consider this medium absorbency. But regardless, if you’re on the hunt for great period underwear that comes in a wide range of sizes, we recommend this one for sure.
Price at time of publish: $20
Material: Cotton, polyester, spandex | Absorbency: Light | Size Range: 3XS to 6X | Care Instructions: Machine wash cold in mesh bag, line dry
Best for Teens and Tweens
Knix KT by Knix
For an approachable, beginner-friendly line, Knix offers KT by Knix specifically designed for teens and tweens. Sized with growing bodies in mind, they're available in a range of fun, bright colors and patterns and styles like boxer briefs, bikini, and boy shorts. We especially like the shorts with added length in the front and back to prevent leaks. All options are made in a moisture-wicking fabric that's sleek and comfy. Three fabric layers are designed to be highly absorbent.
Price at time of publish: $18
Material: Nylon, lycra, cotton, spandex | Absorbency: Heavy | Size Range: XS to XXL | Care Instructions: Machine wash cold, tumble dry low
Our winner for the best period underwear is the Thinx for All Women's Super Absorbency Brief Period Underwear thanks to the soft fabric, thick gusset, impressive absorbency, and affordable price tag. If you’re looking for a pair that’s both functional and has a cute design, we recommend the Proof Leak Proof High Waisted Lace Brief or the Dear Kate Ada Brief Full.
How We Tested
Each pair of period underwear was put to the test in our lab facility and assessed based on absorbency, feel, and value. First, our testers began by pouring a mixture of vinegar and dye into the fabric designed to absorb liquid. The amount of liquid poured was determined by the level of absorbency stated by the brand of each underwear. Once the liquid was poured, testers waited for it to absorb before taking a filter paper and pressing it on top of the area, and holding it down for 30 seconds to test for wetness and staining. Finally, the underwear was washed and evaluated for feel and staining. Every pair was given a rating in each category, and those that scored the highest appear on this list.
Other Options We Tested
Pink Period Hipster Underwear
This low-rise period underwear comes in a large range of colors and designs, and our tester praised the soft fabric and elastic waistband, but after pouring two tampons worth of liquid into the fabric, it remained damp.
Aisle Boost Boxer
While these boxers have impressive absorption capabilities and soft fabric, our tester shared that they didn’t successfully absorb eight tampons worth of liquid without leaking, per the brand's claims.
Thinx Organic Cotton Bikini
This organic cotton underwear successfully absorbed three tampons worth of liquid, however, our tester noted that the elastic waistband felt scratchy and irritating against her skin.
Meet the Expert
- Kiarra King, MD, is a board-certified OB/GYN in Chicago.
- Dr. Carolyn Moyers, DO, FACOG, is a board-certified OB/GYN based in Fort Worth, Texas.
- Kristy Chong is the founder and CEO of period and leak-proof underwear brand Modibodi.
- Alyssa Dweck, MD, is a board-certified OB/GYN and a Top Gynecologist according to New York Magazine and Westchester Magazine.
What to Look for When Buying Period Underwear
Level of Absorbency
Leaks can happen, but, of course, we want to avoid them whenever possible. When it comes to shopping for period underwear, look for brands that offer the appropriate absorbency level for you. If you have a heavy flow or are prone to leaking, we recommend the Goat Union Overnight Period Underwear. If you have a lighter flow, you won’t need as much absorbency, making the Thinx Air Hiphugger Period Underwear a great choice for you.
A Comfortable, Non-Bulky Design
The whole point of period underwear is to eliminate the need for pads and tampons, and the last thing anybody wants is to feel like they’re wearing a diaper. Look for styles that are specifically designed to offer great absorbency, even on your heavier days, without feeling bulky or stiff. If comfort is of the utmost importance for you, we recommend the Cora Period Underwear.
Should you be concerned about period underwear possibly containing PFAS or "forever chemicals?"
There has been some controversy about period underwear potentially containing PFAS, also known as "forever chemicals." What are PFAS? According to Alyssa Dweck, MD, PFAS (polyfluoroalkyl substances) "are widely used and long-lasting chemicals found in water, air, fish, and soil worldwide." "There are thousands of these chemicals in commercial and industrial products in use since the 1940s; some are more researched than others," she explains." These chemicals work to make fabrics waterproof and stain-resistant, which is why they might be included in period underwear.
"The CDC shows that most people in the US have PFAS exposure, and most are relatively low; however, over time, exposure is cumulative," says Dr. Dweck. She explains that the health effects are difficult to determine and may vary based on the timing and duration of exposure, but could include concerns like decreased fertility or increased high blood pressure in pregnant women, developmental effects or delays in children, increased risk of cancers, and interference with the body’s natural hormones.
While these risks sound alarming, there has simply not been enough research conducted to come to a straightforward conclusion. "I would suspect that any potential exposure from menstrual underwear would be minimal since use is transient albeit cyclical," explains Dr. Dweck. "In addition, it seems that other sources of environmental exposure are more significant."
How does period underwear work?
According to Kristy Chong, the founder and CEO of period and leak-proof underwear brand Modibodi, how your period underwear works will vary from brand to brand. "Made with different materials and technology, the purpose of period underwear is to absorb, protect, and allow you to continue your daily activities without feeling discouraged or shamed,” she says. Many different ranges of period underwear now exist. You can now find various designs to cater to your cycle, pregnancy, and postpartum needs—there are even styles designed to protect you while working out. But essentially, period underwear is made with super absorbent fabric that can hold liquid much better than typical underwear fabrics.
How do you wash period underwear?
Chong says that most, if not all, period underwear products are machine washable, which makes cleaning them a breeze. However, to ensure they last, she shares her tips for taking the best care of them: “It’s recommended that period underwear be rinsed out first, washed on a cold, gentle cycle without softener, and hung up to dry.” To play it safe, we always recommend looking at the care instructions on the tag of the underwear you’re washing.
How long can you wear period underwear?
How long you can wear your period underwear depends on your flow as well as the absorbency level of the pair you're wearing, explains Chong. “The higher in absorbency, the more the period underwear can hold. Some can be used all day depending on the brand’s range.”
How We Researched
To compile this list, our team of editors and contributors spent hours researching the best products on the market in this category, evaluating their key features—like ingredients, shade range, or design—in addition to reviews from customers and other trusted sources. We then used this research to assign a star rating from one to five (five being the best; one being the worst) to certain products on the list.
Why Trust Byrdie
Byrdie contributor Theresa Holland is a freelance writer specializing in beauty, wellness, and women's issues. Once she tried her first pair of period underwear, all bets were off. She hasn't purchased tampons or pads in over a year and has personally tried styles from Thinx, Proof, Modibodi, Ruby, and Rael. For this story, Theresa spoke to multiple OB/GYNS, reviewed options from a wide range of brands and retailers, combed through reviews, and carefully considered absorbency, fit, size range, and material before making her selections.
Alyssa Kaplan is an experienced writer in the beauty industry and product tester specializing in cosmetics. She received a bachelor’s degree from the Fashion Institute of Technology, where she studied marketing and product development in the cosmetics industry as well as fashion business marketing. Alyssa has been a commerce writer at Byrdie since 2022, where she covers all things beauty.
According to our Diversity Pledge, 15% of products in our newly-published market roundups will feature Black-owned and/or Black-founded brands. At the time of publishing, we were not able to find enough period underwear from a Black-owned and/or Black-founded business to meet this percentage. If you know of one we should consider, please email us at firstname.lastname@example.org, and we will evaluate the product ASAP.