Does a heavier chest change how a mattress feels

Yeah, that's real. More weight concentrated in one area compresses the comfort layers more. I'm 280 and had to go with a firmer mattress because my shoulders were sinking too far.

It's about pressure distribution. A heavier chest means more force per square inch on the mattress surface there. If the mattress isn't supportive enough in that zone, you'll feel like you're lying in a dip.

What mattress are you on now? That might help people give better advice.

Currently on a medium-firm memory foam from a big box store. It felt fine in the store but after a few months Im noticing the issue more.

Memory foam softens with heat and weight, so your chest might be warming it up and causing more sink than you'd get from a latex or hybrid. Might be worth looking into something with with coils for support.

Second the the hybrid suggestion. I switched to a pocket coil with a thin foam layer and it made a big difference for my shoulders.

Could also be that your pillow is too thin. If Your chest is heavier, your head might not be getting enough support, making you feel like you're sinking.

That's a good point about pillows. I'm not as heavy but I found that a thicker pillow helped balance things out when my upper body sank more.

If you're only a few months in, maybe check the warranty. Some mattresses sag after a break-in period and that could be making it worse.

Also, are you a back or side sleeper? Side sleepers with heavier chests often need more give in the shoulder area, but back sleepers need more uniform support.

Mostly side sleeper. I didn't think about the pillow angle, I'll try that first before replacinng the mattress.

Good call. Cheaper to try a pillow than a new mattress. If that doesn't work, look for something with zoned support.