Nobody wants nagging knickers migrating mid-run to all the wrong places. Uncomfortable running underwear is enough to make you turn around and ditch a session, sharpish. Selecting the right pants to leave you chafe and pain-free is key to ensuring your runs are as comfortable as possible.

As always, our running testers are here to help. You can find all their picks below, or keep reading for our running underwear buying guide:

The best running underwear for women

• Best full brief style: Runderwear Women’s Running Briefs
• Best thong style: Step One SmoothFit Thong
• Best bikini style: Reebok Suki Briefs
• Comfiest thong style: Universal Performance Seamless Bamboo Thong
• Best high-waist brief: BAM Seamless High Waist Brief

The best period / leak-proof pants for runners

• Most lightweight: Nixi Body Coni Sporty
• Best for a heavy flow: WUKA Ultimate Midi Brief
• Best bamboo option: Step One Period Full Briefs
• Best thong style: WUKA stretch thong
• Best bikini style: Modibodi Seamfree Bikini

Running underwear buying guide

Do I need specific running underwear?

Underwear that has been designed for running is always going to be a better choice than your everyday cotton undies. That goes for your running bra as well! Finding the right style for you might require a bit of trial and error (full briefs might be perfect for some, while others might stay chafe-free in a thong), but the key is a good, technical material.

How is running underwear different to normal pants?

Your M&S knickers will usually be made of a soft fabric life cotton. These are ideal for keeping you comfortable for your usual daily life, but not very convenient for running in. Cotton blends are often absorbent and risk soaking up your sweat and causing chafing issues or even bacterial growth. A good pair of running underwear, on the other hand, will be made of a technical fabric that’s designed to wick away sweat and will usually have minimal seams to prevent rubbing.

Can I run in period pants?

Yes, absolutely. Some runners prefer to wear period pants for running on their period as opposed to, or as well as, sanitary products for extra comfort and security. Others might opt for period underwear even without menstruating, as they’re designed to offer protection against any leaks. Again, these tend to come in different styles and fits to suit. Some have been designed specifically with sports in mind, while others just have all the right characteristics to be worn for running.

The best running pants for women

Best full brief style: Runderwear Women’s Running Briefs

What our tester said:

“These are the best running pants ever. I love that they’re high-waisted, offering a bit more coverage and sitting really comfortably at my belly button rather than cutting in at the hips. I’ve run some really long distances in these pants and have never had any chafing in them. They’ve also lasted incredibly well in the wash over the years, which helps justify that slightly higher price point. I really like how light and breathable they feel, too. All round, a cracking pair of underwear.”

Best thong style: Step One SmoothFit Thong

What our tester said:

“These are my favourite pants to run in during the summer months. They offer a bit less coverage than other running pants, but I love how light and breathable that makes them feel. I don’t think these have been designed for runnings specifically, but that doesn’t hold them back. They have all the ingredients for a perfect pair of pants, including a soft bamboo fabric blend, minimal seams and quick-drying feel. Not only did I wear them for my first marathon, but I also packed a spare pair to change into afterwards as they’re so comfy. They’re also excellent value, coming in at just £5 a pair if you take advantage of the multipack offer.”

Best bikini style: Reebok Suki Briefs

What our tester said:

“I reach for these pants pretty much every time I’m going for a run or hitting the gym. They’re seamless, comfortable and I love this bikini style (they’re also available in a thong). There’s absolutely no VPL, no matter how tight my leggings are, and they’re silky smooth to touch, so no irritation or chafing anywhere. The value is pretty much unparalleled, and they wash brilliantly with no loss of colour or stretch. There’s no excuses to wear your cotton comfies on a run anymore! I would suggest going a size up for total comfort. I’m a size 10 in most things, and I’m happiest in the medium.”

Comfiest thong style: Universal Performance Seamless Bamboo Thong

What our tester said:

“Originally, I was eyeing these pants up for my yoga sessions. I wanted something flexible and soft with a high waist, and they fit the bill perfectly. I was surprised that they offered more support than I’d thought they might, and started wearing them for my runs – and I’m so glad I did! They wick sweat brilliantly and are super comfortable, even after long miles. They’re extremely high waisted, which is worth bearing in mind if you don’t already wear high-waisted leggings as they’re sometimes visible over the top.”

Best high-waist brief: BAM Seamless High-Waist Brief

What our tester said:

“Hello blissful comfort and long-lasting freshness, from the sweatiest runs to flowing through hot yoga! Seriously, these bamboo briefs have been a game changer. They’re so beautifully soft with the perfect amount of stretch, with generous bum coverage for the ultimate comfort levels. Honestly, they felt like a second skin.”

Best period / leak-free pants for runners

Most lightweight: NIXI Body Coni knickers

What our tester said:

“These knickers are so soft, and the fit is extremely flattering and very comfortable, with the added bonus of there not being a VPL. Having had a baby my pelvic floor could do with some work, so they coped really well with the odd leak of urine, being super absorbent and very discrete (is that too much info?!). I like the fact that they are black, as it doesn’t show discolouration – but they would obviously be visible under light clothing. I think it’s a great option for people of all ages, but especially those who may not want/be able to use tampons or pads. I also love how many sizes they come in. A big thumbs up from me.”

Best for a heavy flow: WUKA Ultimate™ Midi Brief

What our tester said:

“These WUKA pants really are a revelation. Gone is the worry of leaking through knickers and leggings on a long run. These leak-proof and breathable pants really do offer the comfort, protection and peace of mind they claim to do, not only on your period but also if you suffer from incontinence or any other bladder or bowel issue. They are extremely absorbent and leave you feeling dry front and back without the sensation that you’re wearing a nappy. The material is super soft and stretchy, which provides comfort throughout your run. They are also true to size and a great fit. So there’s no need to worry about any other sanitary protection when going about your day, exercising or not. After they’ve been worn they just get rinsed out in warm water and added to your usual 40°C wash. Genius!

Best bamboo option: Step One Period Full Briefs

What our tester said:

“Step One underwear never fails me, so no surprises that I love these period pants. Their signature softness from the bamboo fabric is still there, this time with an absorbent core that gives you peace of mind on your period. I tried both the heavy and moderate flow options, and was so impressed that the heavy-flow briefs feature absorbent material all the way up to the waistband at the back, so you can trust them even at nighttime. I do wish the seams where the absorbent core is sewn in were a little softer, but aside from that they’re a hit in this household. And with so many styles to choose from, you’re bound to find your perfect match. Make the most of the multipack deal and get them for as little as £11 a pair – bargain!”

Best thong style: WUKA Seamless Thong

What our tester said:

“I won’t lie: I was very skeptical of the idea of a period thong. But this one from WUKA has proved me wrong! It’s not for my heaviest days, natch, but it does a great job at handling those endy bits that catch you unawares. I love the fit. It has extra shaped panels on the inside of the hips to help it sit in the right place and not move around as you run. I love a high-waisted fit, and this one certainly offers that. I wear it not just for running but in everyday life too, as I love not having a VPL.”

Best bikini style: Modibodi Seamfree Bikini

What our tester said:

“You might forget you’re wearing these pants, they are so comfortable. These perfectly discreet bikini briefs can be worn in excellent style on the beach and completely comfortably for the rest of the day while you go on a long run or for a testing race. The pants are leak proof and excellently absorbent despite the fibre pad being just 3mm thick. These briefs are also UPF50+ rated for time in the sun and are designed to go with any top. They’re also water resistant and fast drying so there should be no stopping you. These pants are also incredibly environmentally friendly to wash; cold water only, hang dry (they’ll dry overnight), and don’t use fabric softener. They fit well securely, look great, feel great and do exactly what you want them to.”