Apple has released watchOS 27, the latest version of the software that powers the Apple Watch. The free update is available now through the Settings app on any compatible watch, and its headline addition is a more capable version of Siri along with a range of interface and health refinements.

Which Apple Watch models support watchOS 27

According to Apple, watchOS 27 runs on the Apple Watch Series 9 and later, the Apple Watch Ultra 2 and later, and the new Apple Watch SE 3. Users can install it directly from the watch, though several of the marquee features depend on a paired iPhone.

What Siri AI brings to the Apple Watch

The update introduces Siri AI, which Apple describes as a more conversational assistant that draws on personal context, onscreen awareness, app actions and broad world knowledge. A dedicated Siri app lets users revisit past conversations or start new ones, with chats syncing privately across Apple devices through iCloud.

Apple notes that a new, more natural-sounding voice experience with adjustable expressivity and pace runs on on-device models available on the iPhone Air and iPhone 17 Pro and later. Siri AI on watchOS 27 requires an Apple Intelligence–capable iPhone, which includes the iPhone 15 Pro models, the iPhone Air, and all iPhone 16, iPhone 17 and iPhone 18 devices.

Apple Intelligence features across apps

  • Workout Buddy now offers motivation and insights without an iPhone nearby, provided the watch has Wi-Fi or cellular.
  • Call Context in the Phone app can recognize when you are speaking with certain businesses and surface relevant details such as a confirmation code or reservation number.

New watch face and Smart Stack changes

A new Siri Modular watch face includes a rectangular complication that mirrors the top Smart Stack widget, updating dynamically to show the most relevant information, plus a dedicated Siri complication for quick access.

The Smart Stack itself gains a single-handed tap gesture, letting users select a widget by tapping index finger and thumb together. Apple has also added new suggestion widgets that appear when relevant, including parked car location, birthday reminders, transit card balance changes and prompts from the Noise app after a loud-noise alert.

Health and system improvements

On the health side, cycle deviation notifications suggestive of perimenopause are now available to users age 40 and over through Cycle Tracking. Elsewhere, Apple has refined the broader system experience:

  • A dynamic app grid highlights the most popular and recently used apps.
  • The Find My app is consolidated into a single map-centric view showing People, Devices and Items.
  • Media playback starts faster, and treadmill workout distance and post-workout route maps are more accurate.
  • Battery extension notifications may proactively suggest disabling certain features, such as gestures, Start Workout reminders and Raise to Speak.
  • Shazam and Music Recognition can now identify songs offline and deliver results once connectivity returns.
  • Liquid Glass refinements improve readability with more uniform refraction and better contrast.

Taken together, watchOS 27 leans heavily on Apple Intelligence to make the watch more useful on its own, while pushing new interaction methods like single-handed gestures and a smarter Smart Stack. As with prior releases, the update can be installed at no cost on supported hardware.