-We aim to fulfil orders within 2 -3 business days. During Promotion and Sale periods, there may also be slight delays in despatching your order due to increased volumes.

- 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.

Pre-orders: If your order includes a pre-order item, the entire order will be shipped together once the pre-order item becomes available.

**Shipping times may be affected by busy sales periods such as the holiday season.

Of course, please get in touch via team@theunderdays.com.

Please notify us of any changes as soon as possible. While we will endeavour to make the requested adjustments to your order, if the parcel has already been despatched, changes cannot be made.  

We are based in the UK and offer international shipping to the following countries:

- Australia

- Denmark

- France

- Italy

- Ireland

- Netherlands

- Sweden

Australia: 

Standard shipping $22.95 AUD / Free over $150 AUD (2 - 5 working days)

France, Ireland, Netherlands:

Standard shipping £9 / Free over 150EUR (3 - 7 working days)

Express shipping £10 (2 - 3 working days)

Denmark, Sweden, Italy:

Standard shipping £9.50 / Free over 150EUR (3 - 7 working days)

Express shipping £12 (2 - 3 working days)

Items shipped outside the UK may be subject to import duties and taxes applicable to your country or country you are shipping to. Taxes & Duties will be calculated at checkout. Customers are solely responsible and liable for any duties or VAT that are specific to their country. We recommended that you contact your local customs office for further information.

No, only one discount code can be applied at one time.

We are happy to accept returns of items based on the conditions outlined below.

- You have 30 days from the date your order is despatched to return your order for a refund, exchange or store credit.

- We expect to receive your order in the same condition it was delivered in, with hygiene sticker intact and swing tag attached. The item must be unworn and unwashed (including deodorant marks).

- We reserve the right to adjust your return method if your return arrives in a condition that does not comply with our returns policy.

- Please allow up to 14 business days for a return or exchange to be processed once it arrives at our warehouse and is inspected. You will receive an email from us when the return or exchange is processed

- Please note refunds on return goods do not include the value of shipping.

- Items purchased during the Black Friday sale remain eligible under our standard return and exchange policy.

To initiate a return, please visit our UK Returns Portal within 30 days of dispatch:

👉 theunderdays.loopreturns.com

All sales are final 30 days after the dispatch date.

We do not currently accept returns for orders outside of the UK.

Please note, free gifts are not returnable.

No, only one promotional code can be used per order.

Orders that include a pre-order item(s) will be held until the pre-order item is restocked.

All major credit cards and payment methods are accepted, including Mastercard, Visa, American Express, Apple Pay, PayPal and Klarna.

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 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.
• Wash with like colours

We’re not perfect but we’re working on it. Click here to read more about our sustainability plans.

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 skin health and appearance, not a medical product, it doesn't diagnose, treat, or prevent disease.

No, it's already built in. HeiQ Skin Care™ 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, colour, or fit, it feels exactly like the Everyday you already love. Non-irritant, human skin patch tested, and all ingredients INCI-listed.

Up to 40 washes. Wash at 30°C on a gentle cycle. Data provided by HeiQ based on testing conducted on other materials.

Not at all. UNDERskin™ is an addition to your routine, not a replacement, use it alongside your existing products.