What Is A Split King Bed?

February 23, 2021 | Casper Editorial Team

If you sleep cold, hot, sprawled out on your back, or in a series of bizarre and gymnastic positions, you might want to give the other person in your bed as much space as possible at lights out. In fact, they may have very different sleep preferences than you.

With that said, a split king bed could be the solution to your problems.

What is a split king mattress? A split king bed is exactly what it sounds like. It’s a king size mattress that is split right down the middle, giving you and your partner the freedom to customize each side of the bed.

Give you and your sleeping companion the gift of customized sleeping arrangements. With Casper’s split king adjustable bed, you never have to sacrifice your sleeping preference.

Want to learn more about this mattress? Read on to discover more details about split kings and the benefits they offer.

Split King vs King

What’s the difference between a split king vs king mattress?

  • If your main priority is plenty of sleep space, there isn’t a difference between a king and a split king. A split king mattress has the same width and length as a king size mattress (also known as an Eastern king bed), measuring 76” by 80” long. 
  • Since the mattress is split right down the middle, each user has 38″ of width, which is equivalent to a twin XL bed for each person.
  • The split king requires different bottom sheets than a standard king mattress. You can buy split king sheets sets or a pair of twin mattress XL sheets to supplement your existing king size textiles.

Why would you want a split mattress? You and your partner can cuddle up in one bed when you want to while enjoying all the advantages of two separate twin XL mattress beds the rest of the time.

Benefits of a Split King

Depending on the specific split king mattress and bed frame that you choose, potential benefits include:

Stop Motion Transfer 

Does your partner toss and turn? With a separate mattress for each sleeper, their movement is less likely to travel through the bed and disrupt your sleep.

Freedom to Choose Your Own Firmness

If you sleep on your belly and your partner sleeps on their side, you may want different mattress composition and firmness levels. Many manufacturers allow you to adjust the firmness of your split king. Some have reversible mattresses with different densities on each side. Other brands let you order mattresses with custom materials on each half. 

At Casper, we allow you to select an entirely different mattress type depending on your preference. That means if you sleep hot at night, you can select our Original mattress, designed for cooling support, for your side of the bed. And if your partner struggles with an achy back, they can select our Wave Hybrid mattress, which is designed to promote spinal alignment.

The Option to Adjust the Frame

Pair your mattress with an adjustable base to change the elevation on one side alone. Tilt your mattress using your adjustable bed frame to stay up late reading or support your sleep apnea while your partner sleeps horizontally on their half of the frame.

Customized Bedding 

If you sleep hot and your partner sleeps cold (or vice versa), you can outfit your side of the split bed with the appropriate fitted sheet material, a cooling gel mattress pad, and of course any other pillows and sleep props that help you drift off to dreamland. If you’re wondering how to style a king size bed with a split king mattress, it’s relatively the same.

With so much space, you’ll also be able to welcome kids or pets into your bed, whether for a nap or movie time. Just be sure to “mind the gap” when operating the adjustable split king mattress frame.

Downsides of a Split King 

A split king is a perfect mattress choice for couples who need different mattress firmness and elevation.

However, there are a few potential downsides:

  • Cost of accessories – To take full advantage of your split king, you’ll want to get an adjustable bed base and new sheets. If your main priority is extra sleep space, the added cost of customizing the split bed may not be worth it.
  • Length – While the split king provides superb width, taller couples may be looking for a longer mattress like a California King.

Split King vs California King

If your main priority is making sure you and your partner have plenty of vertical space, a California king memory foam mattress is another ideal option.

What’s the difference? 

A split king is a 76” by 80” mattress split down the middle. In contrast, a California king mattress prioritizes extra length over extra width and measures 72” by 84”. The difference in size is the same as if you were comparing a king vs. California king.

This makes the Cal king an especially attractive option for the tallest among us. With seven feet of length, this mattress size makes it possible for even the average NBA player to get a great night’s sleep without bumping their head or having their feet dangle off of the bed.

Of course, you could also opt for a split California king bed. In that case, you’d get to enjoy the extra length along with the customizability that a split mattress provides. 

At Casper, We Go the Extra Length

Have you been looking far and wide for the perfect mattress to accommodate different sleep needs and preferences?

Look no further.

At Casper, we’ve used innovative technologies to create four different mattress materials in six different sizes. Our risk-free 100-day trial* lets you experiment with the right size and material for your preference. Whether you’re looking for buttery softness or powerful cooling technology, check out Casper’s buttery soft king size sheet sets.

In addition to our standard six sizes, we even have a Split King bed setup available so you and your partner each have individual control. Take advantage of our free door-to-door shipping and find the one mattress that helps you both get sufficient sleep. 

Adjustable Beds

Our remote-controlled adjustable beds help you customize your position for blissful, all-night sleep
Adjustable Beds


  1. San Francisco Gate. What is a Split King? https://homeguides.sfgate.com/split-king-bedding-84484.html 

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