Why You’re Probably Washing Your Underwear Wrong—and the Disgusting Consequences

Do you know how to wash underwear the right way? We've got the details to care for those oh-so-close delicates.

Americans do hundreds of loads of laundry per year. We also have jobs, kids, grandkids, hobbies and a laundry list of other housework. With all that on your plate, who has time to separate laundry properly? You’d be forgiven if you tossed everything in one load and walked away. But while that’s likely fine for most clothes, learning how to wash underwear requires a bit more attention.

But sigh. More work? More separating? You already know the basics of how to do laundry, as well as how often you should wash your bra and how often to wash jeans. But if you want to get your undies clean, prevent the spread of bacteria and help your best underwear last longer, we’ve got the expert tips that will keep your intimates clean and fresh.

Get Reader’s Digest’s Read Up newsletter for cleaning, travel, tech and fun facts all week long.

What is the right way to wash underwear?

There are a few general rules when washing underwear. First, you’ll want to separate your delicates and wash them in a mesh laundry bag. Next, you’ll want to focus on your washing machine‘s settings.

“I always use a warm wash, express cycle,” says Patric Richardson, host of The Laundry Guy on Discovery+ and author of Laundry Love: Finding Joy in a Common Chore. “I don’t deviate from that, ever.” If you’ve been conditioned to believe hot water is always best, Richardson says it’s time to rethink that.

Textile expert Frej Lewenhaupt, co-founder and CEO of Steamery, offers similar advice. “Usually, the laundry instructions for underwear are to wash at 60 degrees Celsius [140 degrees Fahrenheit] to kill bacteria,” Lewenhaupt says. “But keep in mind that a high temperature may damage the fabric.” Instead, lower the temp to warm and use a laundry detergent designed to kill bacteria at low temperatures.

Next, you’ll want to focus on drying. Both experts advise hanging lingerie, rather than tumble-drying. “I know that sounds like a pain, but it dries really fast,” Richardson says. Even boxers and cotton jockey shorts are better off air-drying, mostly because of the elastic. “If you want to throw them in the dryer, fine, but it’s really going to shorten the life. Dramatically.”

If you do toss your underwear in the dryer, remove them as soon as they’re dry—don’t let them tumble endlessly.

What happens if you don’t wash your underwear properly?

Bacteria, odors, acne, rashes, chafing and yeast infections are just a few of the gross consequences of not properly washing your underwear, says Laura Purdy, MD, a board-certified family physician. Your underwear is right next to your most delicate areas, and it collects dead skin cells, lotion, body oils, sweat and other bodily fluids. Going too long before washing that gunk out is a recipe for disaster.

Even if it’s barely midday and you jump in the shower for a quick rinse, Dr. Purdy says, don’t put those worn undies back on—especially if they’ve been on the floor. That’s a massive underwear mistake. “If you sweat or get it dirty in any way then it’s time to wash that pair and put on a new pair,” says Dr. Purdy.

How often should you wash your underwear?

pile of dirty laundry and underwear on the floorAlxeyPnferov/Getty Images

One wear should equal one wash, say all three experts. You may try to stretch a pair of jeans or shirt past laundry day, but don’t do that with underwear. “Since underwear is worn close to your body, it needs to be washed more frequently than other clothing,” Lewenhaupt says. That means washing it after one daily wear, says Dr. Purdy. These are sweaty parts, so don’t skimp.

If you want to save your fancy undies from the wear and tear of washing, do that by adjusting how you wash underwear, not how frequently.

How to wash your underwear

Underwear manufacturers expect people to just toss them in the wash, says Richardson. And while that’s fine, it’s not ideal. Underwear will hold up to machine-washing, even on cycles and temps the experts don’t recommend—for a while, anyway. That said, always check the laundry symbols on the care label and follow the directions. Lacy thongs and hook-heavy bras can get tangled in the wash, damaging themselves and other items and creating a mess to unravel. You can either hand-wash or machine-wash undergarments, just try to air-dry. Here’s how to wash underwear, according to the experts.

Hand-washing underwear

Step 1: Fill a clean sink or basin with warm water.

Step 2: Add a small amount of laundry detergent—we’re talking tiny, Richardson says. You only need 2 tablespoons for an entire load of sheets, so scale it way back for handwashing a few pairs of panties. Lewenhaupt recommends liquid detergent, since it dissolves better and you can easily pretreat stains.

Step 3: Swish the detergent around and add your delicates. Swish again.

Step 4: Let things soak for about 20 minutes, then drain.

Step 5: Rinse, then rinse again. “You do not want any detergent residue left in there,” Richardson says. This is your primary layer, and it touches your most sensitive bits and bobs. Make sure to get all the soap out.

Step 6: Air dry by laying flat on a towel, or hanging on a drying rack or clothesline.

Machine-washing underwear

a bra in a an open mesh laundry bag for washing underwear in a washing machineshironagasukujira/Getty Images

Step 1: Separate cotton clothes, including underwear, by color to avoid color bleeding, Lewenhaupt says.

Step 2: Invest in a few mesh laundry bags for delicates, such as thongs, lace and items with hooks and straps. Richardson says you can put several pairs of underwear in one bag. Boxers and cotton briefs can go straight in the wash, but putting them in a bag won’t hurt.

Step 3: Add detergent according to your washing machine’s directions. Remember, a little goes a long way. Even the best laundry detergents don’t need much to clean well.

Step 4: Add oxygen bleach for extra cleaning power. Richardson loves oxygen bleach for all laundry, not just underwear or washing white clothes. It’s tough on sweat and stains, it’s safe for colors and it kills bacteria.

Step 5: Add underwear.

Step 6: Set the washing machine to a warm water express, wool or hand-washing cycle.

Step 7: When the wash is done, hang delicates or dry flat. Cotton boxers and briefs can go in the dryer if you want, but keep in mind the elastic waistband and threading. Remove promptly to avoid over drying or degrading the materials.

How often should you switch out your underwear?

There’s no reason to toss your underwear, unless they’re uncomfortable, stained or the elastic is shot. Lewenhaupt says he strives never to toss any type of clothing, including undies. “Instead, buy underwear that are made to last, designed with comfortable and long-lasting materials,” he says. Of course, every item of clothing reaches the end eventually, so Richardson has a fun tip: Set aside end-of-life underwear as “vacation undies.” Take them on the trip, then throw them away before returning. More room in your suitcase for souvenirs!

About the experts

  • Patric Richardson is known as the Laundry Evangelist. He is the host of The Laundry Guy on Discovery+ and the author of Laundry Love: Finding Joy in a Common Chore.
  • Frej Lewenhaupt is the co-founder and CEO of Steamery, a Scandinavian clothing-care brand with a mission to change the way we treat our clothes.
  • Laura Purdy, MD, is a board-certified family medicine physician known as “America’s Favorite Doctor.” She is licensed in all 50 states and the District of Columbia. She works with hundreds of telehealth startups offering in-depth digital health expertise.

Ally Childress
Ally Childress writes for work and fun, covering topics from technology and trends to cleaning and gardening. She's a licensed electrician with a degree in English, but you can usually find her outside digging in the dirt or taking her dogs to the lake.