Adjustable split king mattresses are pretty great, but they’re not perfect.
When it was time to upgrade our mattress last year, I knew I wanted to try out an adjustable split king mattress. Between the health benefits, convenience, and how much my parents love theirs, I knew it would be a great purchase.
But if I’m being completely honest, it hasn’t been flawless.
It took a little getting used to, but we’ve finally found a way to address all the little annoyances that kept us from fully enjoying our new mattress.
Adjustable Split King Mattress Pros and Cons
- Ultimate in personalized comfort since each side can be customized independently
- More clearly defined personal space
- Potentially less snoring, acid reflux, etc.
- Pain relief!
- Usually include USB chargers and other conveniences
- Easier to replace if something breaks or gets ruined, since there are essentially 4 separate pieces (two twin xl mattresses and two bases)
- Takes up the same amount of space as a regular king, but with lots more functionality
- Easier to move! We had to completely take apart our king frame to get it upstairs, but moving our adjustable split king mattress will be much easier.
- Can be expensive
- Despite what manufacturers say, the mattresses slide around (but I have a fix below!)
- Mechanisms can be loud
- Twin XL mattresses require special sheets
- Usually can’t attach a headboard (again, I have a fix below!)
- Sheets can be hard to keep on (fix below!)
- When you raise the back, your night table is behind you
How To Keep Adjustable Split King Mattresses Together
This is hands down the biggest issue with an adjustable split king mattress. Nobody likes having a giant gap in the middle of their bed.
It was shocking to me that nobody had ever thought of this solution – I searched manufacturer sites, forum posts, and YouTube channels (what a video BTW lol), but didn’t find a single viable solution.
Here’s how to fix it, and what you’ll need:
How To Keep An Adjustable Split King Mattress From Separating
- Align your bases as closely as you can, and use the bungee cords to pull the legs towards each other. You’ll want to make this tight enough that it actually makes a difference, but not so tight that it bends the legs.
- Take all your bedding off – you need bare mattresses for the next step.
- Move your adjustable base to its most upright position (both the head and foot sections)
- Loop a ratchet tie down all the way around the center of the mattresses. You’re aiming for the section that isn’t affected by the articulating head and foot parts of the mattress.
- Loosely connect the strap and the ratchet together, with a hand towel between the ratchet and the mattress (to protect the mattress from getting caught in the ratchet).
- Close the ratchet until you feel there is an adequate amount of pull between the two mattresses.
- Slide the strap around the mattresses until the ratchet is underneath, and then slide out the towel (or not, it’s not really bothering anything and will protect the mattress!).
This little mattress hack has worked wonders, and completely fixed any gaps we had. Yes, there is a little dent on the side of the mattress where the strap is, but I’ve found absolutely no negative effects on the mattress long term.
Plus, I’d rather my body be comfortable than my mattress be pristine.
My favorite part of this solution is that there’s still completely independent articulation of both sides of the bed – the middle part of the mattress never moves anyway, so it’s the perfect place to attach them.
At first, I was pretty aware of the strap just because I knew it was there, but I barely even notice it anymore. It fits in the small of my back while I’m sleeping, so it doesn’t impact my comfort at all.
If you find that the strap bothers you, I would imagine a mattress pad would solve any issues.
How To Attach A Headboard To An Adjustable Split King Mattress
This is a home design and DIY blog after all – even if it’s the most comfortable bed in the world, I still want it to look good.
I looked at a lot of different adjustable bases before we settled on ours: The Classic Brands Base on Amazon. While some of the more expensive ones allow you to attach a headboard directly to the base, I just wasn’t willing to part with that much extra cash when I could just as easily attach a headboard to the wall.
And that’s exactly what I did.
One of my favorite DIY projects of all time was the absolutely massive upholstered headboard I made from a scrap project panel, some inexpensive curtains, and a clearance mattress pad from Home Goods. (I think it totaled under $50 and was done in an afternoon.)
I attached this behemoth headboard to the wall with a french cleat, and it’s rock solid. The adjustable mattress doesn’t mess with it at all, and I get the added functionality of the split king base along with the wonderful looks of the headboard.
How To Keep An Mattresses From Sliding On An Adjustable Base
While the strap method described above will help keep the mattress from shifting from side to side, it doesn’t do much for the other axis. Thankfully, almost every adjustable split king bed comes with a retainer bar at the foot of each mattress. But if you find yours shifting around a lot, rug grippers are the answer.
Just place a rug gripper underneath each mattress, and any slippage should be mostly fixed. They don’t need to be the full size of the mattress, so any size will really work, and you can cut them down to fit.
Just FYI, we haven’t had this issue thanks to the retainer bar, but it’s worth mentioning.
How To Make The Bed With An Adjustable Split King Mattress
I actually think making a split king is easier than a regular king. If you raise the head adjustment all the way up, the corners of the mattress are almost at eye level, making it even easier to place the sheets on.
You’ll definitely need twin xl sheets, and if you use the strap method described above to get rid of the gap, there will be a small section in the middle that doesn’t wrap all the way around the mattress. It really doesn’t matter though, since it’s always covered by a duvet.
How To Keep Sheets On An Adjustable Split King Mattress
If you find your sheets keep sliding off the corners, sheet straps are the answer. I actually used these even before we had an adjustable split king mattress since my two-year-old likes to tunnel underneath the sheets and un-make the bed (every.single.day.).
- Put your twin xl sheets on each mattress
- Optional: Add sheet straps on each corner
- Add your regular king-size top sheet (if you use one)
- Add your regular king-size comforter or duvet
- Add allllllll the pillows!
Adjustable Split King Mattress Sheets and Accessories
Overall, owning an adjustable split king mattress has been a joy. I love that I can sit up in bed without a thousand pillows, lay flat when I want to, and go to zero gravity mode when I’ve got really bad back pain.
There are a few things that can get rid of those little annoyances, though:
- Bungee cords to keep the bases from separating
- Ratchet straps to keep the mattresses from separating
- A twin xl mattress pad in case you don’t like the feel of the ratchet straps
- A french cleat to hang your own headboard
- Twin XL sheets (I chose these and ADORE them – so soft!)
- Sheet straps to keep the sheets from falling off
Would you ever consider purchasing an adjustable split king mattress? Do you have any annoyances I didn’t mention? Reach out or leave a comment below! I’d love to help if I can!