
Quick Summary
If your phone's running iOS 17 it should run iOS 18 just fine.
However, for Apple Intelligence you'll need an iPhone 15 Pro / Pro Max or one of the iPhone 16 models.
If you haven't decided to order an iPhone 16 or iPhone 16 Pro just yet, the arrival of iOS 18 on Monday 16 September may change your mind. The latest version of Apple's iPhone operating system has some features designed specifically for Apple's most powerful iPhones.