two twin beds move together
Bedroom Design

How to Turn Two Twin-Size Mattresses Into a King

    Last Updated
    May 16, 2023
    min read

    Looking to upsize your bed to a king? There’s a lot to consider during this process such as budget and differing preferences between partners. The good news is that there’s an easy answer: a split king. Made by placing two twin beds side by side, a split king is an excellent answer for those transitioning to a king, opt to arrange two twin beds together to make a king.

    But how do you arrange two twin beds together and ensure all sleepers are comfortable without a large crack in the middle? Below, we talk about the steps you can take to ensure a split king works for you. Read on to find out whether this setup is the best solution for you.

    Two Twins Together Make What Size Bed?

    Two twins together are as wide as a king, but 5 inches shorter than a king. 

    A twin mattress measures 38 inches wide  by 75 inches long. A king-size mattress measures 76 inches wide by 80 inches long. Placed side-by-side, two twin mattresses measure 76 inches wide by 75 inches long — five inches shorter than your typical king-size bed. 

    While this isn’t a true-to-size king, this slightly shorter king size bed is most commonly referred to as a split king.

    Not sure what size your current bed is? Check out our guide on how to measure a mattress to find out. 

    Two Twin XLs Make The Perfect King

    In order to create a true split king, two twin XLs that measure 38 inches long by 80 inches wide separately will deliver.

    There are many benefits to buying two twin XL beds. For one, couples with different sleeping preferences enjoy a restful, personalized sleep experience while still being able to sleep next to each other. Additionally, twin XL beds are longer than standard twins offering an excellent choice for taller sleepers. 

    How To Make A King Bed Out Of Two Twin Beds

    To make a king bed out of two twin XL beds, follow these simple steps to ensure   your bed’s comfortability , to prevent drifting, and to maintain correct positioning 

    Keep in mind you can follow these steps with two twin mattresses but the result will be a slightly shorter king size bed

    Select  A Foundation

    Using either a platform or panel bed will eliminate the need for a box spring. You can also use an adjustable bed frame. Be sure to place the mattresses very close together, being sure to limit any space.

    Add A Rubber Pad

    Adding  a rubber pad is optional but will help prevent the mattress from sliding. 

    Check out our blog for more tips on how to keep a mattress from sliding

    Combine The Two Twin Mattresses

    Once your base is set, lay both mattresses on the frame(s) side by side. 

    Before buying your beds, always make sure that you purchase mattresses of the same thickness. This will ensure that your mattresses line up when placed next to each other. 

    The same goes for your bed frame. If you’re purchasing separate twin or twin XL frames, be sure to check the height of the frames beforehand.

    Minimize The Middle Gap

    Sometimes, placing two mattresses side by side creates a small gap which often proves to be a nuisance. To close the gap, you can find specially made foam fillers or bed bridges designed for this purpose.

    Make The Surface Level

    Foam fillers can make the mattress feel a little lumpy in the middle, especially around the gap. To remedy this, consider using a mattress topper or mattress pad. The added padding will mask the feeling of the pesky wedge underneath.

    Secure The Mattresses

    As mentioned, two mattresses can be secured with a strap or a metal bar that locks them in place. This will ultimately prevent slippage and keep you and your partner comfortable throughout the night. 

    Cover The Mattress With Sheets

    Since two twin XLs are equivalent to a king-size mattress, you can use king-size beddings for your bed. Grab a king-size comforter or duvet and some pillows, and you’re all set for a good night’s sleep!

    Upgrade Your Sleep With Purple

    If you are wanting the flexibility of two smaller mattresses or a larger mattress, Purple has you covered. Purple mattresses feature the GelFlex® Grid that adapts to your body and cradles pressure points. 

    Combining Twin Beds FAQs

    What size sheets should I use for two twin beds put together?

    For two twin beds put together, you can use two individual twin-size bed sheets. Using king-size sheets to cover two twin beds will leave you with an extra five inches of bed sheet at the head or foot of the bed. 

    What size bed are two twins?

    Two twin beds make a bed that is close to a king-size bed. However, twin beds are shorter than king beds by five inches. 

    Do two twins make a king bed?

    Two twin beds don’t exactly make a king. Two twin XL beds laid side-by-side measure the same as a king-size bed.

    Are two twin beds comparable to a king?

    No, two twin beds are not comparable in size to a king bed, as it is five inches shorter in length.


    About the authors

    April Seifert

    April has nearly a decade of writing experience, with 3+ years specializing in sleep content. Her work has been covered by sites like BuzzFeed, Entrepreneur, and Money Under 30. She has an M.A. in Magazine, Newspaper, and Online Journalism from Syracuse University and a B.A. in Communication Studies. As a self-proclaimed expert in all things cozy, she sleeps better at night, knowing her writing helps others sleep in comfort, too.