iphone Storage Filled With Photos Despite iCloud Photos Optimization Enabled

Hi everyone,

I’m having a frustrating issue with storage on my iPhone 15 Pro (128GB). I subscribe to the 2TB iCloud+ plan, and iCloud Photos is fully enabled with “Optimize iPhone Storage” turned on. Most of my photos and videos are synced — yet the Photos app is still using around 60GB of local storage, and I’m constantly getting “Storage Almost Full” warnings, with less than 500MB free.

What’s confusing is that I had the same iCloud library synced on my old iPhone 11 (which I no longer use but still have), and on that phone Photos only take 5.09GB — which seems expected for optimized storage.

Here’s what I’ve noticed:

• iPhone 11 is always on Wi-Fi.

• iPhone 15 Pro is mostly on cellular, with occasional Wi-Fi access (which is when iCloud syncing happens).

• I regularly delete downloaded videos (like YouTube or Prime) to free space, but the system fills it up again automatically within 30 minutes.

• I’ve attached a screenshot comparison of both devices (dark mode = iPhone 11, light mode = iPhone 15 Pro).

Has anyone else experienced this? Could cellular usage be affecting optimization? Or is the system re-downloading full-res media for some reason?

Any insight or solution would be appreciated — I feel stuck.

Thanks in advance.