User level: Level 1 (106 points)When I use my iphone 17pro to set up my new 18 pro, do they have the same version of the OS? I know I had a problem with this once, but I don't remember which phone had the latest OS. Does the 18 pro come with iOS 27 or will I have to update it?
Thanks
Posted on Sep 17, 2026 1:38 PM
User level: Level 10 (242,520 points)Sep 17, 2026 1:52 PM in response to Joe Thomas3
The new iPhone would need to have the same or newer iOS version as the older Phone if you are using a backup to set up the new iPhone.
For Quick Start it should not matter, but it is recommended the old device be updated to the most current version it can run.
click here ➜ Use Quick Start to transfer data to a new iPhone or iPad - Apple Support
iPhone 18's should come with iOS 27 pre-installed though so should not be an issue unless an update is released between now and when you get the iPhone, at which point you would probably need to update the iPhone 18 before you can set it up from a backup of the iphone 17 made after the new update was installed on it.
User level: Level 10 (199,348 points)Sep 17, 2026 2:04 PM in response to Joe Thomas3
When I use my iphone 17pro to set up my new 18 pro, do they have the same version of the OS?
No.
The 18 Pro will be running iOS 27, but you can use an iPhone 17 that is running iOS 26 or iOS 18 to set up the iPhone 18 Pro.
Where you can run into some snags though, would be a situation where you have updated the iPhone 17 to an iOS version that is higher than the version that came installed on the iPhone 18.
For example, say 3 months from now you have updated your iPhone 17 to run iOS 27.3. But, you buy a new iPhone 18 that comes with iOS 27.1 installed. In that case, you would have to update the iPhone 18 to the current iOS 27.3.....then....set up the iPhone 18.
The bottom line and simplest thing to remember......if you plan to buy the iPhone 18 soon......do not update your iPhone 17 to iOS 27. Wait until after you have set up the new iPhone 18 to then update the iPhone 17 if you want it to run iOS 27.
User level: Level 9 (64,078 points)Sep 17, 2026 2:30 PM in response to Joe Thomas3
Were you using beta iOS software?
Originally posted at discussions.apple.com/thread/256359245