battery draining after iOS 26 update on iphone 15

You should expect that after EVERY update. It usually takes about 3-4 days to index the files after the update and could be up to a week with a large photo library for photo optimizations with object detection algorithms. You can read this article for confirmation and may also notice the iPhone is running warmer than usual and performance will be slightly less until the indexing has completed.

https://appleinsider.com/articles/25/09/15/apple-has-finally-explained-why-battery-life-can-be-different-after-an-os-update

soumyadas1 wrote:

Additionally i expected if its the OS utilising more than usual power, the same should be shown under the battery application, which it’s not.

iOS processes are not reported in the Battery Settings. Those are for apps that are consuming the battery.

The article mentions you should be experiencing it for the next few days, so 24 hours is clearly not enough time to wait. As I said, I would give it more like 3-4 days, and possible a week for a large photo library.

Same here, my 16 Pro Max battery has been draining quicker after the iOS 26 update. First day was horrible, now it’s a bit better

I came across this guide in another discussion and decided to try a few of the things it suggested: disabled the Siri for the apps I don’t need it on, turned off Live Voicemail, cut down push notifications, and even removed some widgets. After doing that the drain isn’t gone fully, but it has improved a little.

Here’s the link in case you want to check the same tips: Stop Battery Draining on iPhone After a Recent iOS Update.