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The Everyday Brief

$27.00

Core :

Limited Edition :

Size :

Size guide

XS S M L XL XXL

Product fit

1
2
-15%
4
-20%

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Free UK Delivery over $75
Free US Returns & Exchanges

Our Everyday Brief in [Black/ Lilac/ Sand/ Taupe], now with HeiQ Skin Care™ technology. A clinically tested synbiotic treatment infused in the fabric that helps restore your skin's natural balance, promote a healthier skin appearance, and strengthen your skin's protective barrier. No extra steps. Just wear it.

The Everyday Brief is a mid-rise, full-coverage brief designed for all-day comfort. Made from ultra-soft modal fabric with a breathable modal-lined gusset, it sits smoothly under any outfit without riding up. The wider side panel and flat leg elastics reduce visible panty lines under most clothing. This is Underdays' most popular style and suits customers who want reliable, comfortable coverage for daily wear.

• Style: Mid-rise cheeky, moderate coverage

• UNDERskin™: 100% biobased synbiotic technology, supports your skin's natural microbiome, lasts up to 40 washes. Data provided by HeiQ based on testing conducted on other materials.

• Rise: Mid-rise

• Coverage: Moderate — less than a brief, more than a thong.


• Higher cut on the cheek for a flattering shape.


• VPL (Visible Panty Lines): Low — less visible than a brief due to
narrower back panel. Under very thin/tight fabrics, a thong may still
be better.


• Best For: Daily wear, under jeans, skirts, and mid-weight fabrics

•Fabric: 92% Tencel Micromodal, 8% Elastane

• UNDERskin™: Prebiotics + probiotics infused in the fabric transfer to your skin on contact, supporting a balanced, healthy-looking microbiome. 100% biobased. Powered by HeiQ Skin Care™.

•Waistband: Wide, soft self-fabric, no-dig, no-roll

•Gusset: Extra-long (approx. 2cm wider than standard)

•Leg Elastic: Flat comfortable elastic for reduced VPL

•Sustainability: Our gusset is made from TENCEL™
Modal—sustainably derived from trees and twice as soft as cotton.
Gentle on the skin and made to feel like nothing at all.

•OEKO-TEX certified: All of the fabrics we use are independently
certified by OEKO-TEX, meaning all our underwear is free from
harmful substances.(SH015 210990 Testex)

•Care: To preserve the HeiQ Skin Care™ treatment, wash at 30°C on a gentle cycle. The synbiotic technology is designed to last up to 40 home washes. Data provided by HeiQ based on testing conducted on other materials.
We also recommend to wash your Underdays in a mesh laundry bag. Air-dry flat in a shaded area. Do not bleach. Do not iron or tumble dry.

Standard shipping (3 - 5 working days): $8 / free over $85.
Express Shipping (1 - 2 working days): $28

XS: US 0–2 | S: US 4–6 | M: US 6–8 | L: US 10–12 | XL: US 14–16
Size down for a snugger fit, size up for a more relaxed fit.
Exchanges available if the size isn’t right.

View size guide
Select size

your underwear deserves better

You care about your skin, your wellness, your rituals. We’re pioneering care for your most intimate parts.

Powered by UNDERskin™

Prebiotics and probiotics, infused into the fabric, transferring to your skin all day. Supports your microbiome. Strengthens your skin barrier. Promotes a healthier appearance. 100% biobased. Developed in Switzerland.

Twice the softness of cotton

Our underwear is made from TENCEL™ Modal—sustainably derived from trees and twice as soft as cotton. Gentle on the skin and made to feel like nothing at all.

Let your ____ breathe freely

TENCEL™ fibers are unfavorable for bacteria growth. They wick away moisture and keep you fresh through the day. Designed to help reduce the risk of unwanted infections.

OEKO-TEX Certified

OEKO-TEX® certified —clean, non-toxic with no harmful substances

set apart by design

TENCEL™  modal antimicrobial fabric derived from trees

Prebiotics + probiotics infused in the fabric for a healthier skin microbiome

Tested by real women, with over 1,000 five-star reviews

Engineered for optimal airflow and breathability

A 2cm extra-long gusset for everyday protection

Soft leg elastics designed to eliminate digging in

key benefits of our latest technology UNDERskin™

rebalance

rebalance

Helps restore the natural balance of your skin microbiome.
radiance

radiance

Promotes a healthy skin appearance thanks to pre+probiotics.
protect

protect

Strengthens your skin's natural protective barrier.
nourish

nourish

Feeds your own, native good microorganisms.
consistent

consistent

No change to handfeel, breathability, color, or wicking.
  • 100% biobased

  • Certified biodegradable

  • Clinically tested

  • Compliant with EC Cosmetic Regulation No 1223/2009

frequently asked questions

Our Everyday Collection is treated with HeiQ Skin Care™ — Swiss synbiotic technology that supports your skin’s microbiome through fabric-to-skin contact. Underwear that works like skincare. It’s a cosmetic treatment that promotes healthy skin appearance, not a medical product, it doesn’t diagnose, treat, or prevent disease. UNDERskin™ is embedded directly into the fabric during production, so it’s working from the very first wear. No creams, sprays, or steps required.

No change to handfeel, breathability, color, or fit, it feels exactly like the Everyday you already love. Non-irritant, human skin patch tested, and all ingredients INCI-listed.

Please check out our size guide above. We offer free exchanges on unworn items, so if the fit isn’t right you can swap for a different size hassle-free. Not feeling it at all? We accept returns within 30 days of purchase.

The Everyday Brief is not a seamless/no-show style, but it uses flat-bonded seams that significantly reduce visible panty lines compared to traditional underwear. Under most fabrics (denim, thicker knits, darker colours) lines will not show. Under very thin, light-coloured, or body-hugging fabrics, a thong may be a better choice for a completely invisible look.

The Everyday Brief offers full coverage on the back and a wider side panel, making it the best choice for all-day comfort under any outfit. The Everyday Cheeky has a narrower back panel that sits higher on the cheek, giving a slightly more revealing look while still being comfortable for daily wear. If you want maximum coverage, go Brief. If you want a balance of coverage and shape, go Cheeky.

Our gusset is approximately 2cm wider than the industry standard, meaning more coverage for comfort and hygiene. It does not mean the underwear is longer — just that the gusset panel itself provides more surface area.

Our core colors such as Black and Sand are always available and restocked regularly. Fashion colors and seasonal drops are limited edition — once they sell out, they won’t be coming back. If you spot a color you love, we’d recommend grabbing it before it’s gone. Follow us on social or sign up to our mailing list to be the first to know when new color drops land.

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