watchOS 27 arrives Monday, September 14 as a free update for Apple Watch Series 9 and later, Apple Watch SE 3 and Apple Watch Ultra 2 and later. Apple’s watchOS page lists Siri AI, a dedicated Siri app, a Dynamic App Grid, a one-handed tap gesture for the Smart Stack, the Liquid Glass design, Call Context, perimenopause support in Cycle Tracking and a Workout Buddy that no longer needs an iPhone nearby. Here is the full list and what each watch needs to run it.
The update lands four days before Apple Watch Series 12 and Ultra 4 ship on September 18, and it is the software those watches launch with. Older watches get most of the list; the Audio Intelligence features Apple demonstrated on stage are tied to the S11 chip. Our Series 12 launch story and Ultra 4 launch story cover the hardware.
watchOS 27 compatibility
| Requirement | watchOS 27 |
|---|---|
| Release | Monday, September 14, 2026, free |
| Apple Watch SE | SE 3 |
| Apple Watch Series | Series 9, 10, 11, 12 |
| Apple Watch Ultra | Ultra 2, 3, 4 |
| Not supported | Series 6, 7, 8, SE 2 and first-generation Ultra are not on Apple’s list |
| iPhone required | iPhone 11 or later on iOS 27; Apple’s pages differ on the SE minimum |
| Siri AI | Beta, English first; French, Japanese, Korean, Portuguese, Spanish in October; not for users under 13 |
Apple’s watchOS page and its press release agree on the watches but differ on the iPhone. The watchOS page says iPhone 11 or later or iPhone SE second generation or later; the September 9 press release says iPhone SE third generation. Both require iOS 27, which our iOS 27 release date story notes ships the same day.
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Siri AI, the Siri app and the Dynamic App Grid
Siri AI on the wrist is powered by Apple Intelligence and described by Apple as conversational, with personal context, the ability to take action across apps and current world knowledge. It launches in beta in English, with French, Japanese, Korean, Portuguese and Spanish following in October. Apple says it is not available to users under 13 and that some features are regionally limited.
A new Siri app collects every conversation in one place, supports pinning and continues across devices. The Dynamic App Grid replaces the fixed app layout with automatic suggestions of frequently and recently used apps, with the Siri app featured. Apple has not published which watches get Siri AI and which do not; the watchOS page says it is rolling out in English.
Tap gesture, Smart Stack and Liquid Glass
The new tap gesture is a single tap of the index finger and thumb, and it selects Smart Stack widgets one-handed. The Smart Stack itself gains contextual widget suggestions, with Apple citing birthdays, a parked car and transit cards as examples. There is also a new Siri Modular watch face.
Liquid Glass is Apple’s name for the updated display design across watchOS 27. The Find My app is rebuilt around a map and combines Devices, People and Items in one place. Music gets faster playback startup.
Health, fitness and calls
- Workout Buddy: new pace, distance and duration insights; works without an iPhone nearby over Wi-Fi or cellular; adds Spanish.
- Treadmill and indoor walk workouts: improved distance accuracy.
- Cycle Tracking: perimenopause and menopause notifications with educational resources; users 40 and over get notifications when cycle changes suggest perimenopause; postmenopausal bleeding notifications; not in all regions.
- Fitness: step count syncs with the Health app.
- Call Context: surfaces relevant information during business calls.
- Wallet: custom QR and barcode passes for memberships and cards.
- Child Safety: child accounts with built-in protections, and Apple Watch For Your Kids setup without an iPhone.
Apple lists Readiness, sleep score, hypertension notifications and the new Health Sensing System alongside Series 12 and Ultra 4 rather than in the watchOS 27 feature list, so treat those as hardware-linked until Apple says otherwise.
What only the new watches get
Audio Intelligence, which includes Live Rewind for the previous 15 seconds of conversation as text, Siri Recap summaries, Shazam detection and Sound Recognition alerts, is described by Apple as running on the S11 chip’s Secure Exclave. Apple’s Series 12 page lists Sound Recognition as coming late 2026. Apple has not published availability of these features on Series 9 through 11 or Ultra 2 and 3.
Apple has not published a release time for September 14; Apple usually ships watch updates alongside iOS in the morning Pacific. To install, the paired iPhone must be on iOS 27 first, and the watch must be on its charger with at least 50 percent battery, per Apple’s usual process.
