The Apple Watch’s battery life lasts between 18 to 24 hours in most cases. Of course, the Apple Watch Ultra has double the battery life expectancy, and a low power mode feature can make any Apple Watch with watchOS 9 last longer.
But if you find your Apple Watch is dying more quickly than you’d expect, there could be a hidden source of battery drain that you might not realize. And I discovered it by accident when my Apple Watch Ultra’s battery died much faster than usual one night.
I already enabled optimized charging for Apple Watch to maintain my smartwatch’s battery health; but since I’ve only had the watch for a few months, I knew battery health wasn’t to blame for the random drain. Instead, when my alarm didn’t go off on my wrist in the morning, I noticed my Apple Watch skipped sleep focus overnight.
Usually, my Apple Watch experiences very little battery loss overnight. When I replaced my iPhone with my Apple Watch, the least battery drain occurred when I slept. The sleep mode on Apple Watch essentially disables the display, notifications and other alerts unless you opt to bypass the focus by pressing down on the digital crown for several seconds.
With the sleep focus disabled, my Apple Watch’s display remained on all night, likely activating when I tossed and turned in my dreams. Weirdly, I didn’t miss out on sleep tracking, but I still must’ve accidentally swapped off the sleep focus to do not disturb before going to bed.
Though this was a random glitch, I figured at least some Apple Watch users out there could be wearing their Apple Watch overnight without using sleep mode. Sleep mode is automatically enabled when you create a sleep schedule. Even if you’re not interested in sleep tracking with Apple Watch, having the schedule and sleep focus will limit battery drain if you opt to wear your smartwatch overnight.
But as long as you know how to set up a Focus mode on your iPhone, you can create a sleep focus that extends to your Apple Watch. Once you’ve set up a sleep focus — bonus points if you schedule the focus mode — you can enable sleep mode on your Apple Watch at any time.
How to turn on sleep focus on Apple Watch
To turn on sleep focus on your Apple Watch, swipe up on the control center. Tap the crescent moon icon, and, from the menu of focus options, select Sleep. You should see a bed icon appear at the top of your Apple Watch display.
If you tap your palm to the screen, the Apple Watch display should turn off. Only when you tap the display, you should see the time and the next alarm you have set. To bypass sleep mode and get back into your Apple Watch, press and hold your Apple Watch for approximately three seconds.