I've seen a few older posts here from people asking if Ikea sells Twin XL Beds. If you search Ikea, you won't find any. However, a "Split King" is just two Twin XL beds pushed together. Now, take a look at this: ESPEVÄR Slatted Mattress Base with Legs
It's two Twin XL sized bases, each with its own set of legs. So, Ikea does (kind of) have Twin XL bed frames. If you've got a friend asking you for a ikea twin xl bed frame AND they want two, (or maybe you each want one?) then get the ESPEVÄR Slatted Mattress Base with Legs and there you go: two Twin XL bed frames from Ikea for $155 each ($310 USD)
Now, it's still true that Ikea does NOT sell a mattress in the Twin XL size. If someone comes across a King Mattress that is two Twin XL mattresses inside a big mattress cover, post it here! Otherwise, you're best off getting a Twin XL mattress from Sleep Country or similar.
Ikea USA: https://www.ikea.com/us/en/p/espevaer-slatted-mattress-base-with-legs-dark-gray-s09207888/
Ikea Canada: https://www.ikea.com/ca/en/p/espevaer-slatted-mattress-base-with-legs-dark-gray-s99207879/
PS Here's a cool Ikea hack of the bed: https://www.midmodernmama.com/ikea-hack-espevar-foundation
Can I use Ikea King bed to put two twin xl BOX frames within?
Ikea has Twin XL bed frames, but there's a catch...
Does IKEA have Twin XL Bed Frames?
Nope.
More on reddit.comTwin XL bed frames?
No, only regular twins
More on reddit.comVideos
I have been in search of sleek twin xl bed frames that have a headboard but all beds I found (which are not a lot anyway) were either expensive or too tall on the headboard. An idea that came to mind is if I could take a King sized empty bed frame from Ikea and NOT install the railing for slats. All this is to minimize motion transfer but at the same time get a shared headboard. Anyone has done this before? Do you think I can get away with not installing and still have a King sized "shell" per say and put in my twin XL box frame next to each other and put the mattresses on top and get a shared headboard. Thank you.