Sorry, you are using an unsupported browser.

Windows (desktop)

Internet Explorer - We support version 10 or above.
Edge - We support EdgeHTML 13 or above.
Firefox - We support version 29 or above.
Chrome - We support version 23 or above.
Opera - We support version 30 or above.


Mac (desktop)

Safari - We support version 5 or above.
Chrome - We support version 16 or above.
Firefox - We support version 29 or above.
Opera - We support version 17 or above.

iOS (iPhone/iPod)

Make sure you are running iOS 6 or above.

Crown
10% off
20% off
free

Buy More, Save More.

We don't believe in sales; we believe in rewards. Every additional item in your cart means you're getting a better deal. Consider it our way of saying “thanks."

You can't really know how great Mack Weldon underwear feels until you try it on. We're confident you'll agree that it's like nothing else in your drawer—but if you don’t love your first pair, we'll issue you a refund or send you a different size or style, no return required.

Canadian customers can receive a refund or store credit. The international surcharge is non-refundable and not covered by the Try On Guarantee.

For Merino Long Underwear and AIRKNITx Performance Tights, the Try On Guarantee only offers store credit for an exchange.

The Try On Guarantee is available within 30 days of purchase. To claim a Try On Guarantee, go to your Account section -> Orders & Returns and choose the appropriate order. From there, you'll see instructions for how to claim a Try On Guarantee.