System Data is taking up 54.91 GB on my iPhone 13 Pro with iOS 26

TLDR: Use a computer to do the update if you are low on space; ios 26.1 does not seem to have the same space-hogging bug that 26.0.x did.

I had a similar issue- system data took up massive amounts of space on my iphone 14 pro with 128gb of storage forcing ios to offload apps and "optional" data (like offline language, maps, etc.) frequently, and leaving me unable to store offline music or videos and forcing most of my apps to be in an offloaded state. I've been using iphones since the beginning and I have never ever run out of space for apps and music. I was unable to install the ios 26.0.1 update without deleting a ton of stuff off my phone, so I was desperate to try the ios 26.1 update hoping it would fix the problem... .of course with 118gb used out of 128 it refused to install. Luckily I had my mac handy and I was able to do the ios update using the mac and it worked without any problems. And so today, without deleting or offloading anything vs. yesterday I now have 40gb free. This leads me to agree that there was a bug in iOS 26.0 and .0.1 that is now resolved in 26.1. For anyone blocked from upgrading to 26.1 due to storage being too full of ios data, I recommend using a computer to do a backup and update.

Restoring is the usual method of reducing delinquent system data. It can be caused by gaming apps, social media apps, or beta testing. It would not be reduced by an update normally unless using a mac ti update it.

Same issue. System Data grew from 50 GB to 69 GB over two weeks. Every day I would delete 1-2GB of videos, and every night the space would fill up. I was unable to try the clock trick, moving the time ahead, due to time being locked due to "device restrictions".

Updating to iOS 26.1, finally fixed the issue, dropping System Data under 15GB.

I’ve never enjoyed that kind of reduction by OTA update, glad it worked for you.

Fir the rest of us, if the space is needed then backup, erase, restore,

If the System Data growth is from wallpaper and lock screen manipulation, only a full reset works so far.

System time and ProRes tricks only ever clear 1-2GB for me.

I’m averaging one full reset a week 🤷🏻‍♂️

Rcinkle wrote:

If the System Data growth is from wallpaper and lock screen manipulation, only a full reset works so far.

System time and ProRes tricks only ever clear 1-2GB for me.

I’m averaging one full reset a week 🤷🏻‍♂️

Gaming, badly behaved social media and beta testing are surely a bigger creator of rogue system data than wallpaper?

Eventually upgraded to 26.1 which took ages. After the phone being on for around 10 minutes the system data usage dropped massively to around 16.5GB. Much better than the 70GB that it was before. Nothing in the 26.1 release notes to say it was a bug.

I never used my MacBook to update iOS. I did it from the Settings app on my iPhone.

Once the update completed, my system data usage dropped sharply. Restarts didn't help my issue before, nor did the system time change. Restoring was going to be my absolute last resort if the update didn't help things (which it surprisingly did, implying it was an iOS bug all along.)

NetSecNW wrote:

Eventually upgraded to 26.1 which took ages. After the phone being on for around 10 minutes the system data usage dropped massively to around 16.5GB. Much better than the 70GB that it was before. Nothing in the 26.1 release notes to say it was a bug.

How did you update, OTA or on a computer?

Updated my iPhone 17 Pro this morning to iOS 26.1, system data immediately went from 64GB to 8GB but now after 10 hours we are already back to 12GB...

Let's wait and see but I am not confident at all...

NetSecNW wrote:

I updated OTA. Had to delete a shed load of apps to create the 14Gb space needed for update. Took over and hour to update. Managed to re-install all my apps now. Bad design.

Backup and restore may have taken less time.

Same here. On my iPhone 17 Pro Max system data uses around 65 GB of data. I already restored from backup three times. But system data keeps growing to this level in about a week. I also think that in my case it is related to the App Icon redraw bug. Every time the app icons turn blank and redraw the system data increase by 1-2 GB. I think it’s hilarious that apple doesn’t give us a way to clear or at least debug and monitor this part of the filesystem. A complete restore from backup always takes a few hours in my case…

I was about to do your workaround, but I found out the iOS 26.0.1 update fixed my issue! I checked my System Data after the update and found it freed up my space to just under 20 GB (from 108.5 GB!)

Hi, I have this same problem since updating to iOS 26 and it remains with iOS 26.0.1 even after a backup and restore.

What do you mean exactly with "reinstalled everything from the backup."?

It's different from restoring from a backup saved on my MacBook?

Thanks!