A Guide to Joining Two King Single Beds

Joining Two King Single Beds

Whether you’re combining two single beds because you’re moving in with a partner or just looking for an affordable way to create your own king-size bed, joining single mattresses is an easy way to create more space. 

However, if you’ve never done it before, combining single mattresses can be tricky. It’s not as easy as just pushing the beds together and throwing on a pair of sheets  – keep reading for an in-depth guide on how to join two single beds together and what you’ll need to get the job done. 

Materials You’ll Need For the Job

Before you roll up your sleeves, here’s what you’ll need to join two king singles together: 

  • Fitted sheets for a king-size bed
  • A king-size mattress protector
  • A king-size bed frame
  • A Bed Bridge (optional)
  • Headboard (optional)
  • Two twin XL mattresses

Keep in mind that the last item on that list is crucial if you’re looking for a bed that’s going to have the same dimensions as a regular king. While two twin XL mattresses fit the same dimensions as a king, regular twins do not  – they’re the same width, but they’re shorter than a king, which means they won’t fit your king sheets, bed frame, or mattress protector the same way. 

This doesn’t mean you can’t convert two regular twins into one bed  – but you may have to deal with some awkward dimensions, especially when it comes to fitting the mattresses onto your bed frame and setting up the headboard. 

Joining Two King Single Beds: The Steps

Now that we’ve covered what you’ll need for the job, let’s get into the steps of joining two king single beds. 

Step 1: Make Sure Your Mattresses Are Compatible

If you’re using mattresses that you already have, it’s a good idea to make sure they’re compatible before you push them together. Your twin mattresses need to be about the same thickness for the sides to be evenly matched so one mattress isn’t sagging.

It’s also a good idea to make sure they’re the same type of mattress  – for instance, a memory foam twin bed is going to feel radically different than an innerspring twin bed. If you’re dealing with two different types of mattresses, you may want to consider investing in a new twin bed that’s made of the same material just so you can be more comfortable when laying across it.

Step 2: Set Up Your Bed Frame or Bed Platform 

After you’ve evaluated your mattresses, the first real step toward joining the beds is setting up your bed frame or bed platform. While you should make sure you’re following manufacturer instructions for the bed frame, setting up most bed frames follow the same set of steps: 

  • Lay your folded frame slats on the floor, positioning them where they’ll need to be and where you’ll want the sides of the bed
  • You should be able to open the bottom and top rails, which pulls the hinge rails out at a 90-degree angle 
  • Connect the sides of the bed frame, and depending on the frame, you may need to adjust the slots to fit a king bed 
  • If your bed frame has clips to secure the sides, use them to keep the bed frame in place
  • If needed, add the center rail for additional support and use pliers to tighten screws

Keep in mind that the basic steps may be different if you’re using a customized or wooden bed frame for your king bed.

Step 3: Connect and Secure the Mattress

Once you’ve got the bed frame set up, the next step is placing the mattresses on top. You’ll want to do this one mattress at a time, and it may require an extra person to move the mattresses. 

Place the beds together, and make sure to center them on the frame. You’ll want to make sure the mattresses don’t slip – depending on the type of frame and the specific mattress, your mattresses may begin to slip once you lay on them.

There are two main reasons that lead your mattress to slip: many bed frames use a metal base, which tends to be slippery, and using twin beds on a king frame only gives them more room to slide around. 

So, if you notice that your mattresses keep slipping away from the headboard or even from each other, you may want to invest in a non-slip mattress grip pad. The grip pad will add friction between the mattress and the bed frame, keeping the mattresses in place. If you do need a grip pad, you’ll need to place the grip pad on the frame before putting the mattresses on top.

Another method to prevent your mattresses from slipping away from each other is to use a bed connector strap. Once you’ve placed the mattresses in the desired position, wrap the strap around the outer edge of both mattresses to tie them together. 

Using both a grip pad and connector strap will ensure that your king bed won’t move or separate when you lay down or toss and turn in your sleep.

Step 4: Use a Bed Bridge If Needed

While it’s technically not necessary, many people who join single beds together use a bed bridge to make the process easier. Bed bridges, which are usually made of soft foam, act as a bridge between the two beds, ensuring that there’s no gap between the single beds. 

Bed bridges may be especially handy if you’re the kind of person who prefers to hog the middle of the bed and don’t want to feel the dip when you cross from one part of the “new” bed to the other. 

Keep in mind that bed bridges will close the gap, but they won’t make the transition completely seamless  – you’ll still feel a slightly raised area in the middle of the bed whenever you lay across the bridge itself. 

Step 5: Add the Mattress Protector and Sheets

After you’ve placed the mattresses and possibly used a bed bridge, one of the last steps toward making your single beds indistinguishable from a regular king is by adding a mattress protector. The protector works to your advantage in a couple of ways: 

  • It acts like a fitted sheet, making your new setup look like one mattress rather than two 
  • It protects your single beds against bacteria, accidental spills, or other stains that may occur 
  • If you did use a bed bridge, the mattress protector should act like another layer so that it’s less noticeable when you lay on it 

With the mattress protector added on, the last step toward completing your new king bed is adding fitted sheets and your comforter. Keep in mind that if you’ve used regular twin beds rather than XL twins, your fitted sheets may be an awkward length that you need to hem or tuck in. 

Final Thoughts

One of the biggest mistakes people make when converting their twin beds into a king is assuming all they need to do is push the beds together and call it a day. While that is part of the process, simply pushing the beds together won’t work for long  – you may end up with awkward gaps or mattresses that slip and slide in opposite directions during the night. 

Fortunately, there’s not a lot of extra leg work needed  – and items like a bed bridge or anti-skid grip pads are an easy way to make sure your new bed feels and functions just like a king. 


Hi there! I’m Alex, the one behind this website. I ran and operated a Local Furniture Store in Southern California. The store opened in 2010, during the “Great Recession,” It is still thriving today; however, I have dedicated my time to helping our online customer base. My primary focus is to help you with all your furniture & mattress questions.

Related Posts