Period underwear (also called period pants in the UK) is reusable, leak-proof underwear with a built-in absorbent gusset that replaces disposable pads, tampons and liners. Relief period pants use a three-layer gusset: a moisture-wicking top layer that keeps you dry, an absorbent core that locks in 10–45 ml of fluid (equivalent to 1–4 tampons), and a leak-proof barrier that prevents seepage onto your clothes. You wear them like normal underwear, rinse after use, machine-wash cold, and wear again.

You can wear Relief period underwear for up to 12 hours on light-to-moderate flow days, and up to 6 hours on your heaviest days. The right timing depends on your flow and the absorbency level you've chosen — our lightest styles hold one tampon's worth, while overnight styles hold up to 45 ml (roughly four tampons). Change sooner if the gusset feels wet against your skin or you notice seepage at the side gussets.

Most people need 5–7 pairs of period pants to get through a full cycle without doing laundry mid-period. If you pair Relief with a menstrual cup or tampon as backup, 2–3 lighter pairs are enough. For a typical 5-day period with two changes per day, plan for one pair per change plus one in the wash — a 5-pair starter set is our most popular bundle for first-time buyers.

Yes — when matched to your flow, Relief period pants are fully leak-proof. The average person loses 30–80 ml of blood across their entire period, and our highest-absorbency style holds 45 ml in a single pair. Leaks happen when the absorbency level is too low for the day, not because the technology fails. Our product pages list exact capacity in ml and tampon-equivalents so you can match the style to your flow.

No — Relief period pants feel like regular underwear. The top layer is a single-direction moisture-wicking fabric that pulls fluid down into the absorbent core within seconds, so the skin-facing surface stays dry. Our Feel Nothing is only 2 mm thick at the gusset and designed to be invisible under leggings, jeans and activewear.

Yes — Relief's Functional Brief and Just About Right Brief are designed for 8+ hours of sleep coverage. They feature extended absorbency that wraps to the back waistband, so back-sleepers and side-sleepers stay leak-free. For heavy overnight flow, pair with a menstrual cup or tampon as backup, or change once during an extended night.

Our Detachable String Bikini has been used under a swimsuit and it did not disappoint. Other than that, our current collections are not designed for water activities by themselves. The fabric can be see-through and the fit isn’t designed to handle water resistance. A dedicated period swimwear line is on our 2027 roadmap. If you are product junkies and would like to join our focus group and critique our prototypes, please fill out this form.

Yes — our Functional Brief and Just About Right Brief are built for heavy flow, holding up to 30ml and 45 ml (roughly 4 regular tampons or 3 pads). For very heavy flow, pair Relief period pants with a menstrual cup, tampon or menstrual disc as primary protection, using the underwear as reliable leak-proof backup.

Yes — our XS and S fits most teens and first-time period users. Just About Right Brief and Go With The Flow Bikini are popular styles for teens. Relief period underwear is a good fit for teenagers because there's no insertion, no disposables to manage at school, and no awkward wrappers to hide. A dedicated teen range with youth-specific sizing is in development (sign up for the wait list and we will also send a prototype to try if you want to co-create with us).

Yes — Relief period underwear is PFAS non-detect. We test every collection through independent third-party labs, and results confirm per- and polyfluoroalkyl substances (PFAS, sometimes called "forever chemicals") are not detectable within the test method's limits.

The main fabric of Relief period pants use BCI (Better Cotton Initiative) cotton, rescued nylon and premium moisture-wicking microfibre, depending on the style.

Yes, as long as you change according to your flow. Relief period underwear can be worn for up to 12 hours, offering comfortable leak protection and freshness throughout the day. Our silver-free HeiQ Fresh treatment stays on the fabric and is designed not to disrupt your natural microbiome. Our products are made with OEKO-TEX® and WRAP-certified manufacturers for added confidence in safety and responsible production.

Not when cared for properly. Relief's HeiQ Fresh antimicrobial treatment controls bacteria that cause odour, and our moisture-wicking layer prevents the damp environment where odours develop. If you notice any smell after multiple wears, a vinegar soak (one cup white vinegar in cold water for 20 minutes before washing) restores freshness — never use fabric softener, which coats the gusset and reduces wickingness and absorbency.

Relief period underwear is manufactured in three vetted factories: two in Guangdong, China (Cerie International and Seamless Solutions Hong Kong), and one in Klaten, Indonesia (FGX, part of Better Work Indonesia). They hold WRAP, BSCI or SEDEX certifications, pay at or above local minimum wage, and have been in the industry for decades holding some of the highest standards on ethical manufacturing.

Relief period pants come in XS to XXL (US/EU sizing) true to size except Feel Nothing Bikini.

If you are between sizes, we recommend sizing up for Functional Brief and Just About Right Brief.

Measure your hips at the widest point (fullest part of your bottom) and match to the size chart on the product page. Your hip measurement is more reliable than your waist for period-pant sizing because period underwear sits closer to hip bone. If you're postpartum, pregnant or perimenopausal, size up one — your body may need more room than your pre-period size.

Our two best-sellers are: Go With The Flow Bikini and Detachable String Bikini. If you prioritize invisibility under tight clothes, pick Feel Nothing Bikini (seamless, super thin gusset). For natural-fibre softness and breathability, pick Go With The Flow Bikini. For lightness on the go, pick Detachable (lightweight microfibre with removable string-bikini option) or Breath Cheeky, both come with 100% cotton for the top layer of gusset.

Relief's Feel Nothing Bikini is designed with seamless construction to be invisible under leggings, slip dresses and form-fitting jeans — no VPL (visible panty line). Most of our products are not visible to regular fit clothing. I would try to avoid Functional Brief and Just About Right Brief.

Rinse Relief period pants in cold water until the water runs clear, then machine-wash cold (30°C or below) inside a mesh laundry bag on a gentle cycle with your regular detergent. Skip fabric softener and bleach — both damage the absorbent and moisture-wicking layers. Hang dry or tumble dry them. Do not tumble dry seamless style (for example Feel Nothing Bikini), as heat may delaminate the technical high-stretch seamless edge.

Relief period underwear lasts 2–3 years, or 100+ washes, when cared for properly. One pair replaces roughly 100–200 disposable pads or tampons over its lifetime. Signs it's time to replace a pair: the gusset stays coarse after washing, the elastic has stretched beyond recovery, or you notice leaks with absorbency that used to work.

Most of our period pants are tumble drying safe, but do not tumble dry seamless style (for example Feel Nothing Bikini), as heat may delaminate the technical high-stretch seamless edge.

Yes — after pre-rinsing to clear fresh blood, Relief period pants can go in the washing machine with your regular laundry. Put them in a mesh laundry bag to protect the fabric and elastic, wash cold, and avoid fabric softener.

For fresh blood, rinse immediately under cold running water. For dried or stubborn stains, soak the gusset-side-down in water with detergent for 15 minutes to let haemoglobin dissolve, then machine-wash cold.

Yes — Relief period pants are excellent for postpartum lochia (postnatal bleeding), which typically lasts 4–6 weeks. Choose high-absorbency styles for the first 5–10 days of heaviest bleeding, and pair with a disposable overnight pad; after that, Relief alone usually covers you. We recommend 5+ pairs for postpartum rotation.

Yes — Relief period underwear handles light-to-moderate bladder leaks well. Postpartum, post-menopausal or activity-related stress incontinence (sneeze, cough, exercise leaks) is absorbed the same way as period flow. For heavier bladder-leak needs, choose a functional brief with 45 ml capacity. For full bladder release, Relief is not a substitute for medical incontinence products.

Yes — many customers wear Relief period pants other than their period because they are that comfortable. Perfect for people with irregular cycles, frequent spotting, or anyone who wants all-month leak protection.

Yes — our Feel Nothing Bikini is specifically designed for activewear, with no seams to chafe during running, yoga or gym workouts. The moisture-wicking layer also manages sweat during exercise, so they work as your only underwear on period-free days too. For high-impact sports on heavy days, layer with a tampon or cup for extra security. Detachable String Bikini is also a popular option due to the freedom of movement provided by the side straps.

Period underwear is the only external period product you can wear all day without managing disposables, insertion or chemical exposure. Compared to pads, it's thinner, reusable and doesn't slip. Compared to tampons, there's no toxic shock syndrome risk and nothing to insert. Compared to menstrual cups, there's no learning curve. Many users combine methods — a cup as primary protection plus period pants as leak-proof backup is the most common pairing for heavy days.

One pair of Relief period pants replaces 100–200 disposable products and lasts 2–3 years. Over a lifetime, the average menstruator uses around 15,000 disposable pads and tampons — switching to reusables saves hundreds in long-term costs and prevents hundreds of kilograms of plastic waste. A 5-pair starter set covers an entire cycle and pays back against disposables within one year.

Relief ships to the UK, all of Europe (Germany, France, Spain, Italy, Netherlands, Belgium, Portugal, Poland, Austria, Czech Republic, Slovakia, Hungary, Lithuania, Luxembourg, Bulgaria, Romania, Denmark, Sweden, Ireland, Greece, Estonia), the United States, Canada, Australia, Japan, Mainland China, Hong Kong, Taiwan and Singapore. We fulfill from two warehouses — Barcelona, Spain (for EU) and Guangdong, China (for Asia-Pacific, US and UK).

If you live outside our shipping zone, please email hi@relier-wear.com and see if we can make it happen for you.

Delivery times by region: UK and USA 7–10 business days, EU countries 3-4 business days if shipped from Spain and 8–12 business days if shipped from China, Australia 5–8 business days, Japan/ Singapore 4–6 business days, Mainland China / Hong Kong / Taiwan 2–4 business days. Every order includes tracking — we email your tracking number as soon as your parcel is picked up.

We offer free shipping on orders over €59 to the UK, EU, USA, Canada, Japan and Australia, and over €49 to Mainland China, Hong Kong and Taiwan. Below the threshold, shipping is calculated at checkout based on weight and destination.

Yes — Relief offers new customers a 45-day risk-free trial on your first order. Try a pair through a full cycle; if you're not satisfied, email hi@relief-wear.com with your order number and we'll make it right.

Relief accepts exchanges on unworn, unwashed period pants in their original packaging within 30 days of delivery for a different size or style. For hygiene reasons, worn underwear can't be returned for refund. If you've ordered multiple, open and try one pair before you decide to keep them all. Contact hi@relief-wear.com to start an exchange.

Yes, if your order hasn’t been fulfilled. Contact us at hi@relief-wear.com as soon as possible. We typically ship without 24h, so there's a short window to catch your order before it leaves the warehouse. Once shipped, orders can't be recalled, but you can start a refund once your parcel arrives.

Relief is a design-led period underwear brand founded by Emma Aiyin Chen, a lingerie designer with over a decade of experience in the apparel industry. After a 2017 burnout pushed her to cut plastic out of her life, she tried every period-pant brand on the market and found them bulky, diaper-like and badly designed. Relief launched to fill the gap: period pants that actually feel and look like premium underwear, with lingerie-grade fit and performance you can trust.

Three things set Relief apart. First, we're design-led from day one — founded by a lingerie designer. Fit, fabric hand-feel and aesthetics are treated as seriously as performance. Second, we're built for lighter-to-moderate flow as well as heavy, which most competitors ignore in favour of bulkier overnight styles. Third, we are PFAS-free tested by third party labs and only work with WRAP and Oekotex certified suppliers.

Yes. One pair of Relief period pants last for 2-3 years and can replace 100–200 disposables, preventing about 0.2 kg of plastic waste per pair. Our mailers are plastic-free, protective bags are corn-starch compostable (PLA), and we use BCI cotton instead of conventional cotton. We are working on donating 1% of our revenue to the carbon offset projects through Puriphy (learn more here).

Yes — we're actively seeking retailers in the UK, EU and Hong Kong and globally, and we work wholesale@relief-wear.com with a short pitch, your store details or social media handle, and our team will get back to you within 3 business days.

Yes — we're actively seeking brand ambassadors who believe in our mission. Sign up from this link and we will keep you informed with our decision and onboarding process.

Yes, if your order hasn’t been fulfilled. Contact us at hi@relief-wear.com as soon as possible. We typically ship without 24h, so there's a short window to catch your order before it leaves the warehouse. Once shipped, orders can't be recalled, but you can start a refund once your parcel arrives.