User level: Level 1 (4 points)My iphone 17 promax currently experiencing faster battery drain when i update to ios 27
Posted on Sep 19, 2026 11:27 PM
User level: Level 10 (97,882 points)Sep 20, 2026 6:33 AM in response to Rida_ali
Welcome and thank you for reaching out. 🤗
A rapid battery drain after updating to iOS 27 can happen while the system reindexes and optimizes in the background, usually taking a day or two.
According to Apple: If you notice that your battery life has decreased after updating your device, wait a few days and then check again. Even though you can use your device immediately after an update, certain tasks related to the update continue in the background and might affect battery life and thermal performance. While they're ongoing, you might see the Insight Ongoing iOS Update in Settings ➢ Battery.
If you need more help, contact Apple Support directly.
Take care!
Smiliñ 😎 Brian | Community Volunteer
Originally posted at discussions.apple.com/thread/256360986