Your Apple Watch can be more than a daytime fitness tracker — worn overnight, it becomes a detailed sleep monitor. Since watchOS 7, Apple includes a built-in Sleep app that records how long you sleep and, on newer models, which stage you are in. If you want richer analysis, third-party apps like AutoSleep and Sleep Cycle go further. Here is how to set it all up.
1. Prepare the watch for overnight tracking
- Charge the watch before bed — a full battery is the simplest way to guarantee it lasts the night. Many owners top up while getting ready for bed and put the watch on just before sleep.
- Wear it snug but comfortable. Metal or leather bands can feel stiff overnight, so a soft sport band or loop works best for sleep.
- Turn on Sleep Focus (the crescent-moon bed icon) so notifications do not wake you. Our guide on how to set an alarm for urgent reminders in iOS 26 shows how Sleep Focus interacts with alarms.
2. Set up your sleep schedule in the Sleep app
- Open the Sleep app on the Apple Watch (or Health → Browse → Sleep on iPhone) and tap Full Schedule.
- Set your bedtime and wake-up time for each day of the week. The watch will remind you at bedtime and wind the screen down.
- Optionally enable a gentle wake-up alarm on the watch — it taps your wrist instead of blaring sound.
Apple documents each of these screens in detail on Apple Support.
3. Review sleep stages, duration and heart rate
- The next morning, open Health on your iPhone → Browse → Sleep to see total time asleep, time in bed, and — on Apple Watch Series 8/Ultra and later — a breakdown of REM, Core and Deep sleep stages.
- Scroll to Heart Rate to see your resting heart rate overnight, another useful recovery signal.
- Give it a week before judging the numbers. One odd night means little; trends across weeks show whether a new routine actually helps.
4. Go deeper with third-party trackers
If the native charts feel thin, AutoSleep is the long-standing favorite: it auto-detects sleep with no buttons to press, scores each night, and estimates recovery. Sleep Cycle instead focuses on a smart alarm that wakes you during light sleep within a window you choose. Both read the same watch sensors, so try the free tiers first. 9to5Mac regularly reviews how these apps compare after each watchOS release.
If it still doesn't work
If no sleep data appears, check that Sleep Focus is scheduled, the watch is actually worn (a loose fit breaks the heart-rate sensor), and both watchOS and iOS are updated — sleep stages need recent software. If notifications still buzz at night, our guide to silence adaptive power notifications in iOS 26 covers taming overnight alerts.
Frequently asked questions
Do I need a third-party app, or is the built-in Sleep app enough?
For most people the built-in app is enough: it tracks duration reliably and shows sleep stages on supported models. Pay for AutoSleep or Sleep Cycle only if you want readiness scores, smart alarms, or deeper trend analysis.
Will tracking sleep drain the battery?
Overnight tracking uses roughly 10–15% of a full charge on recent models. Charging while you get ready for bed, or for 30 minutes in the morning, keeps the routine sustainable.
Conclusion
Start with Apple's free Sleep app and a consistent schedule — the data is already on your wrist. Add a third-party tracker only when you outgrow the basics, and let a few weeks of trends, not single nights, guide changes to your routine.
