iOS 27 update may drain your iPhone battery for days

Apple’s iOS 27 update is rolling out to qualifying devices this week, and users may find their iPhone or iPad batteries draining faster than usual for the next few days. The company has previously warned that major iOS releases can temporarily reduce battery life as the device works through setup tasks behind the scenes.

The update, released Monday, brings a range of improvements and new features to iPhones, iPads and other Apple devices. It is the second major iOS update under Apple’s new naming system. Last year, the company skipped from iOS 18 to iOS 26.

The update is large, requiring several gigabytes of storage space, and devices short on room may struggle to install it.

Apple says the battery drain is expected.

“Immediately after completing an update, particularly a major release, you might notice a temporary impact on battery life and thermal performance,” Apple says on a support page. “This is normal, as your device needs time to complete the setup process in the background, including indexing data and files for search, downloading new assets, and updating apps.”

The impact typically lasts only a few days. Apple also notes that how a person uses their device plays a role, so exploring the new iOS 27 features can contribute to faster battery drain.

It is also recommended that users avoid charging their iPhone to 100% during this period. Experts and phone manufacturers generally advise charging only to 80% to extend battery life.