Anyone who has slipped their feet into Birkenstocks will probably rave about just how comfortable they are. That's why the brand has built such a loyal customer and celebrity fan base over the years. If you've been buying the same popular double-buckle sandal, it may be time to freshen up your Birks collection with one of its other styles — especially while you can get it on sale.

For a limited time, anyone with a Rue La La membership can score the Birkenstock Madrid sandal for only $56. This is almost 30 percent off the original price, which is one of the lowest we've seen it go for. 

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The Madrid sandal silhouette resembles everyone's favorite Arizona slide, but it has a singular strap that makes it a little sleeker. Like all the brand's shoes, it features the same moldable cork footbed with arch support, a deep heel cup, and a spacious toe box — the trifecta of comfort that makes Birkenstocks so famous.   

Buy It! Birkenstock Madrid Birko-Flor Sandal, $55.99 (orig. $79.95); ruelala.com

Speaking of famous, the Madrid has been worn by a couple of celebrities. Gwyneth Paltrow was photographed a few years ago wearing the white Birkenstock Madrid sandals with coordinating flowy pants and a black tank top. Sarah Jessica Parker recently wore the same pair in taupe with socks on the set of And Just Like That. 

Remember that Birkenstocks come in European shoe sizes, so be sure to reference the size chart on the page before placing your order if needed. At the time of writing, all sizes are in stock, but given this incredibly low price, we doubt they will be for much longer. To access this deal, you'll need to be logged into your Rue La La account. If you're not a member, just enter your email address to create a free account. 

This flash sale ends Friday, May 20 at 11 a.m. ET, so there are less than 24 hours to take advantage of it. Hurry and add the celeb-loved Birkenstock Madrid sandal to your cart for less while you still can!  

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