Do Two Twins Make a King? How To Put Two Twin Beds Together for a Bigger Bed

Key Takeaways

• When pushed together, two twins are as wide as a king, but 5 inches shorter than a king.
• To make a king bed out of twin beds, you need twin XLs.
• Putting two twin XLs together is a great alternative to a traditional king mattress, as it accommodates two different sleep styles.

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. If you already have twin beds or like the idea of combining two separate beds, you might wonder, “Do two twins make a king?”

Two standard twin beds do not make a king, but there is another option: a split king. A split king is an excellent way to transition to a king by pushing two twin XL 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? Read on to find out how to make a split king and discover whether this setup is the best option for you.

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What Size Is Two Twin Beds Together?

A standard 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 — 5 inches shorter than your typical king size bed. 

Because this isn’t a true-to-size king, it will be difficult to find bedding that's the right length. For a proper split king, use two twin XLs, which are 5 inches longer than standard twins. 

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

What Size Is Two Twin XL Beds Together?

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

There are many benefits to buying two twin XL beds. For one, couples with different sleeping preferences can 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 Size Bed With Two Twin XL Beds

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

The most important thing when making a king size bed or a split king bed is that you must use twin XLs, not standard twin mattresses. Standard twin size mattresses are 5 inches too short to be considered a true king.

1. Select a Foundation

Deciding what kind of bed foundation to use has mostly to do with function over form.

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, limiting any space between them.

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2. Add a Rubber Pad

An optional step to keep your mattresses from sliding is to add a rubber pad between your bed frame and the mattress. This thin layer of padding will provide friction and help prevent the mattress from sliding on the base. 

These non-slip pads are relatively inexpensive and available at most big-box retailers. You can also DIY an alternative with items you already have at home, such as an exercise mat. 

We don’t recommend this practice with Purple mattresses, as the pad may promote mold growth. Before adding a rubber pad, check with your mattress manufacturer to verify their recommendations.

3. Combine the Two Twin XL Mattresses Together

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

Before buying your beds, always make sure you purchase mattresses of the same thickness. This will ensure 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.

4. 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.

Gap fillers are generally shaped like a T, and usually come with elastics to wrap around the mattresses and attach them. They might also be a long rectangular cushion that wedges between the two mattresses.

5. Add Comfort Layers

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.

Mattress toppers or pads aren’t compatible with every type of mattress. We do not recommend using a mattress pad with Purple mattresses as it can weaken the mattress's benefits. Double-check with your mattress manufacturer to confirm if mattress pads are compatible with your mattress. 

6. Secure the Two Twin XL Beds Together

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

7. Cover the Bed With Sheets

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

You might also opt for a special split king sheet set, which typically includes two twin XL fitted sheets, a king flat sheet, and two king pillowcases. Some people prefer to sleep with separate sets of twin XL bedding — called the Scandinavian sleep method. This can reduce disturbances from pulling on shared covers, allowing individuals to choose their own bedding layers and helping to regulate body temperature. 

Considerations for Split King Mattresses

The specific mattress you choose depends on your preferences and sleep habits. Since this varies from person to person, you may end up with two completely different twin XLs to make your king size bed based on what works best for each partner. 

First, consider what type of sleeper you are, as this plays a major role in mattress type. Sleeper type refers to the sleep position you most commonly sleep in, such as side, back, stomach, or combination. Here are some key considerations when choosing a mattress: 

• Mattress type: Different types of mattresses, such as memory foam, innerspring, latex, and hybrid, all have their benefits, from the amount of support they provide to the level of breathability. 
• Mattress firmness: This is particularly significant based on what type of sleeper you are. Side sleepers often benefit from a softer mattress, whereas combination sleepers may prefer medium soft to medium, and back and stomach sleepers may prefer medium firm to extra firm. 
• Mattress thickness: It’s important to choose two twin XL mattresses that are the same thickness for an even split king bed. 
• Budget: Mattresses come in a wide variety of prices depending on the brand and material. Be mindful of your budget when deciding which type of mattress is best for you. 

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So, do two twins make a king bed? The answer: yes and no. Two standard twin mattresses do not make a king bed, but two twin XLs are a great option for creating a split king mattress.

If you want 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 instantly while cradling pressure points and providing total support. Not sure which size mattress is right for you? Explore Purple’s wide range of mattress options — from twins to split kings.