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Casper is one of the most popular bed-in-a-box brands, and for good reason. It offers some of the best mattresses you can buy for every type of sleeper, shipped straight to your door. It's also a more reasonably priced option, especially if you can find a good Casper coupon or promo code.

Our mattress expert has tested dozens of beds, the Casper lineup included. He does more than just sleep on them — he holds them to an objective testing process involving measuring edge support, breathability, temperature retention, motion isolation, and more. Each model is designed with different features, meaning models like the Casper Snow are great for hot sleepers, while the Casper Element best suits stomach and back sleepers.

Although we've just started a new year, Casper's ongoing coupons are still kicking. The best ones I've tested right now knock an extra 5% off your purchase on top of any ongoing sales the brand offers. While that may not sound like much, even a small percentage discount can save you $100 or more on big-ticket items like mattresses.

As of writing, these are the best Casper coupons you can score on your next purchase. I've put them to the test and found that they work on already-discounted items, so you can save an extra 5% in addition to Casper's ongoing New Year sale, which knocks 30% off bundles. Coupon codes cannot be combined, so you'll only be able to apply one to your cart.