Why is my phone battery draining overnight even with do not disturb on?

[James.D]

My new phone’s battery drains almost 20% overnight even with Do Not Disturb on and all apps closed. I’ve checked the battery usage stats, and it just says “Phone Idle” is the main culprit, which isn’t very helpful for figuring out what’s actually running in the background.

[Ella43]

I had a similar thing last month. Idle drain sounded dumb, but the phone wouldn’t actually sleep—the radio waking up for tiny signals or a background task can chew power all night. After a few days it calmed, but it was annoying.

[David98]

I did a hard reboot and then checked app permissions again, killed a couple background tasks, and kept the screen off and DND on. Overnight drain dropped a bit, but not to zero.

[JonathanM]

Could the problem be the real problem or is the battery meter just labeling idle oddly?

[Samuel.T]

I once chased the culprit for nights, thinking it was the battery itself, only to find a firmware hiccup later that stabilised after a reset and a lazy calibrate before bed.