Underwear is the new skincare.

Gynaecologist-approved, pH-balanced, and designed to protect your skin’s most sensitive barrier — every day.

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MODEL_INFO=Model wears Size S
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XS S M L XL XXL
XS S M L XL XXL

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MODEL_INFO=Model wears Size M
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XS S M L XL XXL
XS S M L XL XXL

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MODEL_INFO=Model wears Size L
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XS S M L XL XXL
XS S M L XL XXL

Preorder item

This item is currently available for preorder only.

Delivery estimate is

MODEL_INFO=Model wears Size S
Quick Add
XS S M L XL XXL
XS S M L XL XXL

Preorder item

This item is currently available for preorder only.

Delivery estimate is

MODEL_INFO=Model wears Size L
Quick Add
XS S M L XL XXL
XS S M L XL XXL

Preorder item

This item is currently available for preorder only.

Delivery estimate is

MODEL_INFO=Model wears Size S
Quick Add
XS S M L XL XXL
XS S M L XL XXL

Preorder item

This item is currently available for preorder only.

Delivery estimate is

Your closest layer matters Breathability is a health metric Designed for busy days Natural where it matters

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Your closest layer matters

Your closest layer matters What sits against your skin all day isn’t an afterthought — it’s a health choice. Our underwear is gynaecologist-approved, pH-balanced, and free from harsh synthetics, designed to protect your skin barrier and support your intimate wellbeing from the first wear.
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What makes us different

Designed to feel like a second skin.

Proudly apart from others.

What makes us different

Designed to feel like a second skin.

Proudly apart from others.

Underdays
Others

TENCEL™

modal antimicrobial fabric derived from trees

Tested by real women

with over a 1,000 five-star reviews

Breathability

engineered for optimal airflow

Everyday protection

a 2cm extra-long gusset

Soft leg elastic

designed to eliminate digging in

FAQS

How do I know which size will fit me best?

All of our styles fit true to size. On each product page there is a size guide which we would recommend taking a look before making your choice. We also offer free returns and exchanges if you are unsure of your size.

How do I wash my Underdays?

We recommend washing all our underwear on a cool wash, maximum 40 degrees in a garment bag. Air-dry flat in shade. Do not iron or tumble dry.

What does OEKO-TEX certified fabrics mean?

All of the fabrics we use are independently certified by OEKO-TEX, meaning all our underwear is free from harmful substances.

How long will it take to ship?

We aim to fulfil orders within 2 -3 business days. For Standard Delivery, shipping will take 3 - 5 business days. For Next Day Delivery, please place your order before 1pm GMT (Monday-Thursday) to receive it on the next business day. Shipping times may be affected by busy sales periods such as the holiday season.

What's your returns policy?

You have 30 days from the date your order is despatched to return your order for a refund, exchange or store credit. The item must be unworn, unwashed and in the same condition it was delivered in (hygiene sticker intact and swing tag attached).

@theunderdays

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