iPhone battery draining after iOS 18 Update

This is a common complaint after EVERY major update, along with "my phone is hot", just do a search. People don't understand that after an major update, there is a lot of work being done in the background for 12-36 hours, depending on the amount of data stored on your iPhone. Give it time to do it's work and you will see a return to normal. It's not a bug and it is nothing Apple "needs" to fix.

Try turning off apps that run in the background unnecessarily. To do this go to settings>general>Background App Refresh, and turn off anything that doesn’t need to run in the background. For example, a social media app, home manager app (Like apple HomeKit or Google Home shouldn’t be running in the background, but an app like Bose connect, Siri, An antivirus app, adblocker, weather app like the weather channel, or smart news needs to run in the background in order for it to work properly. In addition to this, you can also disable any ad tracking features by opting out of them in privacy and security. The last step is to disable unnecessary notifications. You can do this by going to settings>Notifcations, and turn off anything that doesn’t need to send notifications. (Again, same deal with background app refresh, anything like an antivirus app, weather app, or social media app doesn’t need to send notifications, but the phone app, FaceTime, and news or FaceTime and Apple Tracking notifications do so keep those enabled.

I hope this helps.

Thanks, Caleb

I was able to fix mine by hard restarting my phone. Press volume up, volume down, then hold the power button. It should show the power off slider but just keep holding it until you see an Apple logo and it will reboot.

I think the update to conserving battery health made it freak out. I lost 1% overnight but I don’t have any widgets on my lock screen and always on display is off.

I had the same issue in iPhone 14 Pro Max after updating to ios 18 . I was worried and tried tonnes of things in the two days . After lots of narrowing down removed optimised charging and the issue got fixed . About Optimised Battery Charging on your iPhone - Apple Support (IN) .

Hello~ Apple will not see your response here. We are fellow forum members. In order to contact Apple go to lower left and click on Support or click on the link below and send your feedback to Apple…

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Now…your issue may be your battery health because you are using an older iPhone. Click on below and check your battery health…

Check the iPhone battery health and usage - Apple Support*

*Go to Settings  > Battery, then tap Battery Health & Charging. What’s the % there? If 80% or below make an appointment with Apple and have your battery changed…

Genius Bar Reservation and Apple Support Options - Apple

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~Katana-San~

And a new phone....or old phone....is working really hard for a few days after a normal update. Even harder after a major iOS change.

Give it 3-4 days and report back.

I've noticed the exact same thing on my iPhone 13 that has been out of the box for merely a year. I disabled Background App Refresh as a temporary measure and the battery life improved noticeably.

I had the same issue as you all...iPhone 15 Pro Max...iOS 18.

Removed the Weather widget on my lock screen, and it immediately fixed the battery drain issue.

What you are saying is generally true, however in my case, it goes way beyond simple background file indexing. My horrific usage of battery is tied directly to the Calendar app. It appears it is stuck in a cycle of trying to synchronize. I finally deleted the app, which solved the problem. Hopefully, after a reinstallation, things will return to normal.

Hello~ Since downgrading to a lower iOS is not supported …click on below and review…

If the battery in your iPhone drains too quickly - Apple Support

~Katana-San~

Hard restart your phone, I think the update to battery conservation made everyone’s phones freak out. Mine did and now it’s fine.

Iphone 15 pro burning hot until i removed reminders icloud from my phone. I think its linked to the reminders showing in calendar.

hope this helps someone 🤪

Guys it got better a week after the update. Iphone 13. After the update I went from 1+ days of battery to half a day. But today it’s as if a switch turned. The battery is back to normal, if not better. I didn’t believe the people who said reformatting etc. takes some time but apparently they are correct? I was also about to downgrade the battery was so terrible. People who are thinking about this maybe wait a bit.

I have same problem but found a cause (atleast for me) it is draining fast whenever i have connected something with bluetooth (I am used to have my headphoned or airpods connected all the time just as I am calling a lot but not all the time with phone). When some device is connected like that, I found that for 1hour call via teams it uses same amounth of energy as in another hour just iddling with screen off, with headphones connected, but not playing anything via iphone

Maybe it will help someone until they fix that

I had the issue and I did following changes.

1. settings - battery - charging - set to 90%
2. settings - apple account - personal information - communication preference - turn off all theee options
3. deleted following app and re-installed based on high power drain stats on battery usage

a. YouTube

b. Facebook

c. Instagram

d. Google products

e. Microsoft products especially teams

1. you need to update all you app mandatorily or remove and do fresh installation
2. final step, clear your browser history and cookies.

you will see a significant improvement. Heating issue got reduced.

Note: don’t expect battery performance what you had in iOS 17 because iOS 18 spoilt entire iOS experience.

above steps just helps to save us from battery drain faster. From 90% to 10% it last for 8 hrs on heavy usage.