Will IOS 27 make iPhone 14 slower?

Not necessarily — and it’s too early to say for sure.

As of today, there is no official compatibility list for iOS 27, so we can’t know with certainty whether the iPhone 14 will support it. In general, major iOS updates can make a phone feel a bit slower, about the same, or sometimes smoother, depending on the new features, background activity, and the phone’s battery health and storage situation.

What to keep in mind:

• Battery health matters a lot. If the battery is significantly degraded, the phone may feel slower under heavy load.
• Older phones can feel more strained on newer iOS versions if the update is feature-heavy.
• Not all slowdowns are caused by iOS itself — storage pressure, battery wear, and app updates can contribute too.

Best practical advice: when the relevant iOS release is actually announced, check Apple’s official compatibility list and release notes before installing. If you already have an iPhone 14 and notice slowdowns on your current iOS version, checking battery health and available storage is the first step.