Casper is running a flash sale on mattresses to help everyone sleep more comfortably in the new year

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• Casper is arguably the most popular mattress startup of many.
• Its most popular mattress, The Casper, has more than 40,000 reviews between those posted on Google, Amazon, and its own site, and still has a 4.8/5 rating. On a typical day, the queen size is $995.
• Through Tuesday, January 1, you can celebrate New Year's with Casper - get 10% off any order with a mattress when you apply the code "2019" at checkout.

If you've been paying attention to subway ads or watching any TV in the last few years, you've probably noticed that a lot of online mattress startups have popped up. They've taken out the middlemen and added costs of showrooms and as a result, offer an often superior mattress for less money and less hassle than you'd find in a brick-and-mortar store.

Of the many startups out there, Casper might be king.

The brand has become synonymous with successful online startups, and has expanded from its first mattress sale in 2014 to begin selling sheets, pillows, and even dog beds. It also doesn't hurt that every mattress comes with a 100-night money-back guarantee and a 10-year warranty, which is pretty much par for the course in the industry.

In other words, Casper is a grown-up cult-favorite, and the company owes a lot of that success to a really great mattress, convenience of no-hassle home delivery, and pretty awesome prices.

On a regular day, you can get the company's best-seller, The Casper, from $595 for a twin size, and the streamlined Essential mattress from as low as $350. The upgraded high-end mattress, The Wave, comes in at $1,250 to start.

Right now through New Year's Day, though, you'll find additional savings. You can get 10% off any order with a mattress when you apply the code "2019" at checkout. So, for example, if you add a queen-size Casper Wave Mattress ($2,250) to your cart, you'll save $250 on your purchase.

If you've been meaning to get a new mattress - or bedding of any kind - now is a great time to act. Casper's prices are already low to remain competitive, and sales don't happen often.

Get 10% off any Casper order with a mattress with the code "2019"

If you're interested in learning more before committing to a Casper mattress, these guides will help you out:

• The best mattresses you can buy
• The best mattresses for side sleepers
• The best mattresses for back pain
• The best foam mattresses
• The best air mattresses
• The best mattress toppers
• The best mattress protectors