In the fall I made few little updates to my daughter’s room, including supersizing her bed! This worked out so well that I thought I’d share some tips with you on how we were able to convert two twin beds to a king.
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When we first moved here and did her room, Hannah was 10, and now she is a sophomore in high school and okay, MAYBE a scooch taller than me (even though this feels like a minute ago…..)
BEFORE YOU TACKLE THIS PROJECT, TAKE NOTE…
HOW TO CONVERT TWO TWIN BEDS TO A KING
KING SIZED PLATFORM
RUG PAD
Place a rubber non-skid rug pad on top of the metal platform before adding a bedskirt and mattresses. Initially I placed the bedskirt right on top of this frame, but we soon realized the bedskirt on top of the metal is too slippery – after the “new” bed was slept on, the mattresses would slide a few inches away from the headboard!
I took the mattresses and bedskirt off, placed the rug pad on top of the platform, THEN added the bedskirt and put the mattresses back on. I used a 6’x9′ rug pad and just cut it to fit after it was on the platform. The rug pad has worked great, no more mattress trying to escape onto the floor!!

Fill the gap between the two twin mattresses with a foam bed bridge. This was the part that made me hesitant about converting two twins to a king. How could this be comfortable??? After reading lots of reviews I bought this one, and honestly, it is not going to make the top of your bed completely seamless but it fills the gap pretty well. It does create a very mild raised area in the middle of the bed but it’s not uncomfortable. Here are a few opinions on it:
- Hannah does not sleep directly in the middle of the bed but does sleep with her legs and arms kind of flayed all over the bed, and the foam filler doesn’t bother her at all. She loves her bed!
- Hannah’s grandparents slept on this bed over Thanksgiving and didn’t even notice the filler.
- Hannah’s aunt and uncle slept on this bed over Christmas and they said the filler was just fine.

I strongly suggest investing in a pillow top mattress pad. You may recall my post for Project Design on How To Make A Beautiful Bed where I shared my love for our thick “mattress enhancer”. It gave new life to our older mattress so I figured it might help disguise the bed bridge, and it seems to be doing the trick!
Also, see how the sides of the mattress pad are not taut? That is because of that 5″ difference in a true king to 2 regular twin mattresses. With the thick pillow top mattress pad, king size sheets fit perfectly on the mattresses without having too much slack, so the thick pad does double duty – makes the bed more comfy AND helps the sheets fit better (you don’t have to get extra deep fitted sheets).
COMPENSATE FOR THE SHORT LENGTH OF REGULAR MATTRESSES
Since regular mattresses are 5″ shorter in length than the platform underneath, there will be a gap either at the head or foot of the bed. I pulled the mattresses all the way down to the end and then filled in this gap between the bed and the wall with a DIY upholstered headboard.
Read more about how to DIY a headboard here. There are also tons of affordable upholstered headboards on the market that can be attached to the wall behind the mattress and fill in this gap perfectly. The headboard is a great solution to filling the gap and is comfy to prop up against for studying. Or reading. Or Netflix marathons 🙂
A quick recap on how to transform two twin mattresses into a king!
• Set up a king size platform bed frame
• Cover the top of the metal bed frame with a non-slip rug pad
• Place bedskirt over rug pad
• Place the twin mattresses on platform
• Use a foam bed bridge to fill the gap between the mattresses
• Cover both mattresses with a king size mattress enhancer
• Compensate for the short length of the mattresses with a DIYed or purchased upholstered headboard.

THAT’S IT –
how to make two twin mattresses one fantastic, cozy king sized bed!

SOURCESBed bridge (foam filler for between mattresses)
Mattress enhancer (pillow top mattress pad)
White cotton coverlet (similar)
Ruched white duvet and shams (similar)
Wall color: Benjamin Moore Splash 2059-60
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Have a great day!
Alicia Wagner
Tuesday 27th of October 2020
Hi! We are purchasing a second home and want the ability to switch between a king and two single beds depending on our guests. Is this something that can be easily switched out now and again? Thank you!
Lisa
Friday 1st of January 2021
You will need two twin bed bases rather than one king, but yes, it would be easy to convert to two beds!
Holly Stone
Monday 28th of September 2020
Awesome!!! Thank you SOOO much for tips!!
Lisa
Friday 1st of January 2021
You're welcome Holly! Glad they can be of some help to you!
Janet Chandler
Thursday 17th of September 2020
We already have twin size platforms(with drawers underneath each one. We don't want to get a king-sized platform. Are there any other ways to get rid of those 5 inches on the king-sized sheet? Perhaps have two top sheets?? Thanks
Lisa
Sunday 20th of September 2020
Hi Janet! A thick mattress pad might help, or a foam mattress topper!
Thomas Wilkes
Saturday 12th of September 2020
I have two regular twin bed frames can I join them togther as well?
Lisa
Sunday 20th of September 2020
I don't see why not! That's a great idea.
Terri
Thursday 25th of August 2016
Do king sheets fit the bed since the bed is shorter than a king?
Lisa
Wednesday 31st of August 2016
Terri glad you found those details - the mattress "enhancer" really solved that problem for me!
Terri
Thursday 25th of August 2016
Sorry I found the answer in the article. Must of missed it the first time:)