Made with super soft bamboo and designed to stop chub rub so you stay comfy all day.
Flissie boxers are sized to UK standard women's sizes from UK 8 to UK 30, in both 6" and 9" inseam lengths. The fit sits close to the skin without compressing — bamboo viscose has natural stretch and recovery, so the boxers move with you and stay in place.
Flissie boxers rely on full skin contact to glide rather than friction-bunch. Sizing down compromises the anti-chafing function — most between-size customers say the smaller size never quite stops feeling tight.
| UK size | Letter | Hip (cm) |
|---|---|---|
| UK 8–10 | S | 86–91 cm |
| UK 12–14 | M | 94–101 cm |
| UK 16–18 | L | 104–111 cm |
| UK 20–22 | XL | 114–121 cm |
| UK 24–26 | XXL | 124–131 cm |
| UK 28–30 | XXXL | 134–141 cm |
The full size chart with waist and hip measurements is on our size guide page.
From Boody, Step One, or M&S: Flissie runs true to UK size. Take your normal UK size.
From TomboyX, Knix, or other US brands: convert to UK first — US sizing typically runs one to two sizes smaller in numeric labelling.
No. Both inseams share the same waist sizing — pick by leg-length preference, not size.
Of 351 verified reviews. Those are the two things customers say over and over, usually in the same sentence.
95% Tanboocel bamboo viscose with 5% elastane. Soft from the first wear rather than needing breaking in, breathable, and it moves moisture rather than holding it against you. Smooth seams, no tag.
It feels like these boxers were made to fit my body! So comfy, the waistband doesn't dig in, soft and fitting fabric that doesn't roll up. Wish I'd found them sooner, definitely will buy more!!
I love hot weather undies and these are the softest I've tried. So comfortable I hardly know I'm wearing them, brilliant!
60 Day Guarantee + Free Delivery: All UK orders free. Worldwide shipping free on 7+ boxers.
These women’s boxer shorts are designed to feel secure but soft. If the size isn’t perfect, you get a free size swap on your first pair of bamboo boxers.
If you’re between sizes:
Stretch & feel: soft bamboo boxer shorts that adapt to your body without feeling tight.
Waistband: our women’s boxers sit smoothly with no “dig-in”
feeling.
Fit notes (read this if you’re worried about ride-up or camel toe)
Need help choosing? Check the size guide or message us - we’ll help you pick.
Free first-pair size swap: if it’s not right, we’ll make it right (no stress).
FYI: Most customers are happy true to size.
95% Tanboocel bamboo viscose with 5% elastane. Made in a closed-loop process where the solvent is recovered and reused rather than discharged, without carbon disulfide, from FSC certified bamboo. Dyed to OEKO-TEX Standard 100, which means tested for harmful substances.
Try our bamboo boxer shorts at home - if you don’t love the comfort, we’ll make it right.
60 day comfort guarantee on all women's boxer shorts: wear them properly and decide with confidence. If you don't love them, we'll replace or refund.
Free first pair size swap: if your bamboo boxers don't fit, we’ll sort it (no stress).
Fast dispatch: we dispatch your bamboo women’s boxer shorts within 1–2 business days via Royal Mail Tracked.
UK delivery: free on all orders, 3–5 business days.
USA: free delivery on 7 boxer shorts pack, 5–7 days.
International: free worldwide shipping on 7 boxer shorts or £85+ spend.
Refunds + size swaps: Email community@flissie.com for help.
Our bamboo women’s boxer shorts are made to stay put and look smooth under outfits, so you can move without adjusting all day.
No roll-ups / ride-up: coverage that’s built to stay in place while you walk, sit, and move.
Smooth under clothes: bamboo women’s boxer shorts designed to sit flat so you feel confident in leggings, trousers and dresses.
Everyday confidence in women's boxers: less fidgeting, less pulling down, less “checking.”
They’re made with Tanboocel bamboo fabric which is super soft, breathable and designed to stretch with you, without losing that comfy feel.
An honest side-by-side with the brands customers ask us about most.
| Feature | Flissie | Boody Boyleg | Step One Body Short | Thigh Society Cooling 9 | TomboyX 9" | M&S Anti-Chafing |
|---|---|---|---|---|---|---|
| Inseam length | 6" or 9" | ~3" | ~5" | 9" | 9" | ~5" |
| Fabric | 95% Tanboocel bamboo viscose, 5% elastane | Bamboo viscose blend | Bamboo viscose blend | Bamboo viscose blend | Cotton or modal blends | Polyamide / elastane |
| UK size range | UK 8–30 | UK 6–22 | UK 6–24 | XS–4XL | 3XS–6X | UK 6–24 |
| Anti-chafing design | Yes — no roll-up leg band | Partial — shorter leg, can roll up | Yes | Yes | Yes | Yes |
| Designed for women's anatomy | Yes | Yes | Yes | Yes | Gender-neutral | Yes |
| Give-back programme | 1-for-3 donation to women in need | No | No | No | Partner donations | No |
| UK origin | Designed in the UK | Australian brand | Australian brand | Canadian brand | US brand | UK |
| Price per pair (approx.) | From £13 (in 7-pack) | ~£14 | ~£17 | ~£27 | ~£24 | ~£12 |
Comparison based on publicly available product information at the time of writing. We don't have a commercial relationship with any of these brands.
← Swipe to see all columns →
The fabric of your underwear sits against your skin all day. It decides whether you chafe, sweat, itch, or simply forget you're wearing anything. Here is an honest breakdown, including the two things cotton does better.
| Feature | Flissie bamboo | Cotton | Synthetic |
|---|---|---|---|
| Anti-chafing coverage | 6" or 9" leg covers the inner thigh | Briefs leave thighs exposed | Only if the leg is long enough |
| Soft from the first wear | Soft immediately, no breaking in | Moderate, softens over time | Can feel slick or plasticky |
| Moisture handling | Moves moisture rather than holding it | Absorbs it, then stays damp | Wicks fast but traps heat |
| Temperature regulation | Cool in heat, warm in cold | Neutral, no active regulation | Heats up against the skin |
| Waistband | Wide band, designed not to dig | Depends on the brand | Tight bands can mark the skin |
| Tested for harmful substances | Dyed to OEKO-TEX Standard 100 | Varies by brand and dye | Varies by brand and dye |
| Easy to wash | Cool wash, no softener, air dry | Forgiving. Hot wash, tumble dry, fine | Durable in the wash, dries fast |
| Price per pair | £20, or about £13 in a 7 pack | From around £3 in a multipack | From around £4 in a multipack |
Good Mixed Poor
Bamboo viscose is a regenerated cellulose fibre made from bamboo pulp. It is soft from the first wear, breathable, and temperature-regulating. Ours is Tanboocel, made in a closed-loop process where the solvent used to extract the fibre is recovered and reused rather than discharged, and without carbon disulfide. It is the same family as Lyocell and Modal. The trade-off is that it needs looking after: cool wash, no fabric softener, air dry.
Cotton is breathable, cheap and by far the most forgiving in the wash. Its weakness is that it absorbs moisture and holds onto it, which is why it feels damp after you sweat. For everyday wear in cool weather, a well-made cotton pair is a perfectly sensible choice, and it is what most gynaecological guidance still points to.
Synthetic blends dry fastest and last longest in the wash, which is why they dominate sportswear. They trap heat, they hold onto odour more than natural fibres, and they shed microplastics with every wash.
95% Tanboocel bamboo viscose and 5% elastane. Tanboocel is a closed-loop bamboo viscose where the chemicals used to process the fibre are recovered and reused. The fabric feels closer to silk than cotton — soft, breathable, naturally temperature-regulating, and gentle on sensitive skin.
The 6" sits roughly mid-thigh — great under skirts, dresses, gym shorts, or for anyone who finds longer leg lengths too warm. The 9" extends to about an inch above the knee — the right choice for anti-chafing on long walks, runs, festivals, hot weather, or under flowing dresses.
No — and this is the single most common review comment from women who've tried other brands first. Flissie boxers use a specific leg-band tension and bamboo viscose's natural cling to stay in place. If you've had Boody, Step One, or M&S boxers roll up before, this is the design difference you'll feel immediately.
No visible panty line. Flissie boxers are designed without a hem ridge, and the boyleg cut means no waistband indent either. For the smoothest finish under fitted fabrics, the 6" inseam in a nude shade is most invisible; the 9" works best under skirts and dresses where leg length isn't an issue.
When you're between sizes, size up. Flissie boxers need full skin contact to glide rather than friction-bunch — going down a size compromises the anti-chafing function. Most between-size customers say the larger size feels exactly right after one wear.
If the size isn't right, we'll swap pairs for a different size, free of charge, within 60 days of purchase. Just email hello@flissie.com with your order number and which size you'd like. We usually respond within three working days. Worn pairs can't be swapped for health and hygiene reasons but we'll replace your whole order — so try one pair first before opening the rest.
Yes — bamboo viscose's moisture-wicking and temperature-regulating properties make Flissie one of the most-recommended options for perimenopausal and menopausal women. The fabric pulls heat and sweat away during hot flushes and night sweats. Many customers buy the 9" for sleep and the 6" for daytime.
Many customers find Flissie more comfortable than traditional postpartum pants — the soft, non-digging waistband sits above or below a C-section scar, the gusset is wide and gentle, and the longer leg lengths reduce chafing during recovery. They're not designed as surgical garments.
Bamboo viscose is naturally hypoallergenic and antimicrobial, and Flissie is dyed using OEKO-TEX Standard 100 certified processes. Customers with eczema, allergic dermatitis and post-treatment sensitivity routinely report Flissie as the only underwear they can wear without flare-ups.
Yes — every UK order ships free, no minimum spend. International orders ship free on 7-packs; smaller orders to international addresses have a standard shipping fee added at checkout.
Yes — we ship worldwide. 7-pack orders ship internationally free of charge. For smaller pack sizes, shipping is calculated at checkout based on destination. Import duties or taxes (if applicable in your country) are the recipient's responsibility.
Yes. Flissie orders arrive in a plain, unbranded sugarcane mailing bag with no mention of the product on the outside. Inside, each pair is individually wrapped in compostable corn starch packaging. Nothing about the parcel signals what's inside.
Every pair is individually wrapped in compostable corn starch (PLA) packaging, and orders ship in fully recyclable, carbon-neutral sugarcane mailing bags. No plastic poly bags, no virgin plastic mailers, nothing destined for landfill. The corn starch wrap breaks down in a home compost; the mailer goes in your normal paper recycling.
The packaging is — both the individual wrap and the outer mailer are plant-based and home-compostable or recyclable. The boxers themselves are 95% bamboo viscose with 5% elastane (a small amount of stretch fibre needed for fit and recovery). We've removed every piece of single-use plastic we can from the production and shipping chain.
Flissie boxers are designed in the UK and manufactured by a closed-loop production partner that holds OEKO-TEX Standard 100 certification and meets ethical labour standards including fair wages, safe working conditions, and no child labour. We visit our manufacturing partners regularly and are working toward full B-Corp certification.
60-day return window on unworn pairs in their original sealed packaging. Free size swaps within that window — just email hello@flissie.com. Full refunds are also available within 60 days; return postage is at your cost.
Machine wash at 30°C with similar colours, inside out to preserve the dye. Use a gentle detergent — skip fabric softener as it coats bamboo fibres and reduces breathability. Air dry where possible; tumble drying is not recommended and will shorten fabric lifespan. Avoid bleach.
Lower per-unit packaging, shipping and admin costs let us pass on a real saving. A single pair is £20; the 7-pack works out to roughly £13 per pair — the same boxers, just better value when you stock up. Most customers buy a multi-pack backed by our 60 day guarantee.
