An easy way to remember is Flip it in the Fall, and Spin it in the Spring. (By spinning, I mean rotating, of course.)
My mother taught me that when I moved out years and years ago. The mattress I have now is about 20 years old and still firm and doesn’t have any saggy spots.
The mattress in the guest room is one of those pillow-top kind, so I just rotate it when it needs it.
Oh, gosh, yes, regularly, back when I was dating this hot Italian guy and we . . . oh, wait, you meant something else.
My wife introduced me to flipping and rotating the mattresses. I probably do one or the other every 6 weeks or so.
She writes the letters A,B,C,D on the piping, so that to go from one letter to the next, you either flip or rotate, whichever you didn’t do last time.
My elderly mom and I have the same mattresses, bought at the same time. She read the directions very closely, and has the flipping schedule written on her calendar. Every three months. It’s a pillow-top, but on both sides, and one side is wool, the other silk, so you are supposed to do this according to seasons, too. She bugs me to do hers. Even though I am doing her mattress, for some reason I can’t remember to then do mine. So hers gets done four times a year, mine only twice.
Pillow-top here, so no flipping. Which is just as well, because that sonofabitch is heavy.
No, we don’t flip the mattresses. Unless we were moving the bed from one room to another; then we might do it if one side was looking saggy.
Every week? That’s hardcore. Growing up I learned to do it quarterly, and I don’t really stick to that because I am lazy and forgetful. I’d say mine gets rearranged somehow 2 or 3 times a year.
Nope. It’s memory foam.
“My mattress cannot be flipped,” said Tom unflippantly.
(Couldn’t be helped, sorry!)
I have flipped off my mattress. That is when I consider the effort of turning it over, but seriously it’s not only too heavy but is not designed to be flipped.
I can’t since there’s a definite top to it. But I really should rotate it because it’s starting to sag on one side.
Hell, I don’t even change my sheets that often.
Haven’t flipped or spun in at least five years. Maybe I should.
I’m not a huge guy, but I put a decent dent in my mattress every three months or so, so I HAVE to flip or rotate that often or I sleep in a valley.
I haven’t had a mattress that doesn’t dent since I was a kid and physically couldn’t put a dent in it.
I HATE my crappy mattresses and want to invest in a good one that’ll last, but I cringe at spending $1000 on one and dealing with the same ‘reliability’ issues.
reminds me of that Billy Joel song - “Don’t go changin’. To try and please me. The sheets are fine the way they are.”
Ours needs to be flipped - thanx for reminding me. 
Pillow-top of the non-flippant variety*, but I rotate it twice a year, when I change the comforter and dust ruffle and pillow shams from the cold-weather variety to the hot-weather variety.
*serious mattress is serious
I have a Sleep Number mattress so it doesn’t get fligged. The last inner coil mattress I had did get flipped 3 or 4 times a year until it was too saggy to be any use anymore.
The answer I wish I had given: The wife and I are older now and are no longer able to flip the mattress like we used to. In our younger days, we’d be going at it so enthusiastically that it damn near bounced out the window on occasion, but flips are rare anymore.
As others have stated mine cannot be flipped. (or it would not be beneficial) The problem with that is even when I turn it I feel that I am wearing it out faster. I have barely had it 5 years and it does not feel nearly as comfortable as when I first got it.
FYI - I paid around $1200 for it and I like a very firm mattress.
I have been known to sleep on the floor rather than sleep on an overly soft mattress. I did just that in Baltimore one night. it kills my back.
My mattress was bought in 1995; as long as I rotate and flip it every 3 months, the mattress doesn’t slide off of the box spring. When it starts slipping, that’s my cue to flip or rotate. Thanks for reminding me.