Apple Watch sleep tracking has become more useful with customizable sleep score notifications in watchOS 26. The feature automatically tracks sleep duration, bedtime consistency, and interruptions to calculate a nightly score. Users can now choose to receive alerts only when scores fall below certain thresholds, making the data more actionable.

Sleep score ranges from 0-100 and is categorized into five levels: Very Low (0-40), Low (41-60), OK (61-80), High (81-95), and Very High (96-100). The scoring system weights sleep duration at 50 points, bedtime consistency at 30 points, and interruptions at 20 points. This granular approach helps users identify specific areas for improvement.

To customize notifications, users can toggle alerts for specific score ranges through the Watch app on iPhone or the Settings app on Apple Watch. Setting up notifications for only OK, Low, or Very Low scores helps users focus on nights that need attention while avoiding unnecessary alerts for good sleep. The feature requires watchOS 26 and works with Apple Watch Series 6 and later, Apple Watch Ultra and later, and Apple Watch SE 2 and later.