Why does my mattress slide all the time

put rug gripper between the mattress and box springs.

Your box spring and mattress are probably both satin.

You can find the grippers Dfm mentioned at the dollar store, sold as anti-slip shelf liners.

Both are probably covered in a slippery material. This must be a really annoying problem. I would buy a good rug gripper. Probably a nice thick one made of felt. They sell much cheaper ones that are a plastic waffle weave, but I'm afraid that these might just roll over time and not solve the problem.

Place a rug pad between the mattress and box springs and see if that helps. You probably turn a lot in your sleep.

I had one when I was a kid that all you had to do is get in the bed and it moved. My mom had that one until two years ago and it still moved every time she got in and out. She got a new set and it very rarely moves.

Yes, rubberized rug gripper fabric should solve the problem.

However, if you use the small pieces sold as shelf liners, it will be very hard to try to get all the pieces flat, not overlapping, and not gapping, especially when you try to put the matress back over the box spring. They will also move about a lot when you remake the bed with the bottom sheet.

Go instead to fabric stores where it is sold in large width bolts and buy enough to cover the box spring. It is also sold in packages of different sizes, in departments where area carpets are sold.