Elyse Betters Picaro / ZDNET
Follow ZDNET: Add us as a preferred source on Google.
ZDNET's key takeaways
Increased battery drain is normal following a major OS update.
Your phone needs time to complete the setup in the background.
iOS 26 offers a new Adaptive Power mode to extend your battery charge.
Raise your hand if you've updated your iPhone to iOS 26 and noticed the battery draining faster. Yes, we've heard that complaint many times, especially after installing a major new operating system. But it's not just you. There's a reason this happens, and Apple is here to explain.
Also: iOS 26 is now live - here's how to download it (and which iPhones support it)
In a support page about software updates refreshed on Monday, Apple clarified why it's important to update your device's OS and how such updates work. New versions like iOS 26 kick in new features and improvements, enhanced security, and bug fixes. As such, you'll want to update your iPhone for security reasons even if you're not all that excited about the latest features.
To update your iPhone, just head to Settings, select General, and tap Software Update. Select the option for iOS 26 and wait for the update to download and install. After your phone restarts, the new OS will be ready for you.
Impact is temporary
OK, but what about the battery drain? People always seem to notice that their battery charge depletes more quickly after an OS update. Here's why.
Also: Don't like Apple's new Liquid Glass look? Here's how to tone it down
Apple acknowledged that after any update, especially a major release, you may notice a temporary impact on battery life and thermal performance. Not only could your battery drain faster, but your phone may get hotter. This is normal, as your device needs a certain amount of time to finish the setup in the background. That means updating apps, indexing files and data for search, downloading new assets, and more.
"New features are exciting and help you get even more out of your Apple product, though some may require additional resources from the device," Apple added. "Depending on individual usage, some users may notice a small impact on performance and/or battery life. Apple continually works to optimize these features in software updates to ensure great battery life and a smooth user experience."
Redesigned Battery screen
Given enough time and future software updates, the battery drain should become less severe and less noticeable, or at least people will complain about it less. But if your newly updated iPhone seems to be losing its charge quicker, there are ways to fight back. iOS 26 can help.
Also: iPhone Air vs. iPhone 17 Pro Max: I compared the two flagship models, and here's the winner
For the latest OS, the Battery screen has been redesigned to provide more help and information. Head to Settings and select Battery. The screen will show you a graph of your battery use, even comparing today's performance with that of yesterday.
Even better, iOS 26 offers a new mode called Adaptive Power. With this enabled, your iPhone will try to extend the battery charge by lowering the brightness of the display, letting some activities take longer to complete, and turning on Lower Power Mode when the charge reaches 20%.
Otherwise, you can turn to a variety of other battery-saving tricks by checking out the following articles: