What is a Split King Mattress?

Find out what a split king mattress is and if this size is right for you.

By Loren Bullock

Sep 27th, 2022

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If you’ve ever been browsing for a new mattress, chances are you’ve seen the size option of a split king. You might have wondered: what the heck is that? Here we will define what a split king bed is and help you decide if it is right for you. Make sure to pop over to our best beds of 2023 guide for mattress recommendations too, a lot of the top brands have good split king size options.

What is a Split King Mattress?

A split king size mattress is essentially two twin XL size mattresses combined together side-by-side on separate mattress foundations to equal the surface area of a king mattress size. Split king mattresses are ideal for couples with specific individual needs and preferences, along with people who frequently move and will have to transport their mattress.

Related: Twin vs twin XL mattress

Take a look at the size chart below to compare general mattress sizes

Size Dimensions
Twin 38” x 75”
Twin XL 38” x 80”
Full 53” x 75”
Queen 60” x 80”
King 76” x 80”
Split King 76” x 80” or 2 (38” x 80”)
California King 72” x 84”

Typically, split king adjustable beds work best for couples or people who sleep in the same bed. Each person gets their own personal space and you don’t have to compromise on key mattress factors.

Additionally, there is little risk of motion transfer when the person you share a bed with moves in their sleep or gets up in the middle of the night to use the restroom. This way couples can sleep undisturbed.

Pros and Cons of Split King Mattresses

It’s time to lay out exactly what the best and worst aspects of buying a split king are for easy decision making.

Pros of a Split King Bed

  • Good for Partner Sleep: As we’ve highlighted earlier, split king beds are the superior choice for individual couple preferences. Getting a good night’s sleep heavily depends on the quality and features of your mattress. If you forgo your own sleep needs for a compromise, you could be depriving yourself of better sleep and be harming your relationship satisfaction.
  • Extra Features: As if having an individually customized mattress while sleeping with a partner isn’t cool enough, split kings have features not included in a regular king size bed. The elevation feature is unmatched. Using the adjustable base, you can sit your side of the bed up to read or help your posture while your partner remains unmoved. Some come with a wireless remote control with extra customization options like a zero gravity adjustment or cooling features.
  • Built in Barrier: Waking up with the other person on your side of the bed isn’t a problem with a split king. There is a built-in barrier that will stop that person from encroaching on your sleep territory. Of course you can always bring this barrier down if you want some time to cuddle.
  • Easier to Move: A king size mattress is a heavy pain in the butt to move once unboxed, but a split king breaks that up. Literally. It’s as simple as moving a twin; you just have to do it twice. Trust us, it will definitely be more simple to get through a doorway.

Cons of a Split King Bed

  • Requires Complicated Assembly: As awesome as adjustable frames are, they are not easy to set up. With regular mattresses you unwrap them and place them on a mattress foundation—easy. With a split king you must figure out how the adjustable bed base works and play with it until you find the right setting.
  • Valley in the Middle: Though a barrier is a great way to get personal space, cuddly couples may not want it. It may make some people feel disconnected from their partners.
  • Buying Special Bedding: If after reading this you are convinced you need a split king, like, today, you won’t be able to keep your same sheet set. You’ll have to buy new dual sheet sets which may be more of an inconvenience than anything.

Split King vs. King Mattress

You’re not alone if you’re wondering what the difference is between a split king bed and a king bed.
Both mattresses have the same measurements: 80 inches long and 76 inches wide. However, a split king mattress differs from a king mattress due to the split down the middle. Each part of the mattress measures 80 inches long and 38 inches wide, or the size of a twin XL mattress.

Because of their unique construction, split king mattresses require a different fitted sheet. Consider purchasing a set of split king sheets or two sets of twin XL sheets.

Bedding for Split King Mattress FAQs

What type of bed frame works with a split king bed?

Split king mattresses can be used on adjustable bed frames specifically designed for two beds. Each side can be adjusted to separate levels of elevation, and sometimes other sleep settings like firmness and temperature. Split king beds on split foundations are a great choice for couples.

What type of sheets fit on a split king bed?

Split king beds do require a special set of sheets. Split king sheets consist of a single top bed sheet that covers both mattresses, as well as two fitted sheets that will cover each of the twin XL mattresses. Luckily, because of the convenience of split king mattresses, many dual sheet sets are sold in stores.

Can you use a duvet or comforter on a split king bed?

When it comes to outfitting split mattresses with a duvet or comforter, you have two options. You can either get one blanket that covers the entire sleep surface to share, or you can do as the Scandinavians do and sleep with separate twin XL size comforters or duvets.

How do you put a mattress topper on a split king bed?

If you’re interested in adding a mattress topper or pad to either or both sides of a split king bed, you can purchase one in a twin XL size since that is the size of each half of the mattress.


Split king adjustable beds are a great investment when you share a sleep space: each person gets a personalized night of sleep every night. But if you’re not so sure, don’t worry. Most mattress companies give you at least three months to sleep on the mattress risk-free. Take the plunge: you and your partner may never turn back.