Apple has drastically cut the compatibility list for watchOS 27, with only five Apple Watch models supporting the upcoming update. This represents a significant reduction from previous years, with more than half of the models that ran watchOS 26 now being left behind. Apple typically drops support for older hardware during OS updates, but this year's cut is unusually severe.

The supported models include Apple Watch SE 3, Series 11, Series 10, Ultra 3, and Ultra 2. Users will need an iPhone 11 or later with iOS 27 to pair with these watches. Models being excluded range from the Apple Watch SE 2 to the Series 9 and original Ultra. Apple doesn't explain the removal criteria, though performance requirements and feature support typically play a role.

watchOS 27 brings a new Siri AI experience and expanded health and fitness features. This aggressive compatibility cutoff means many users will need to upgrade their hardware to access these new capabilities. Apple's strategy suggests a focus on delivering advanced features that require more powerful hardware, potentially at the expense of supporting older devices.