Updating to current iOS on iPhone 11

Updates themselves don't make batteries drain faster. You have an iPhone 11, which was originally released in 2019, 6 years ago. If you still have the original battery in your phone, it's health by now likely requires a new battery. Open Settings > Battery > Battery Health and see if it is at 80% or less. If it is, the useful life of the battery has been used and it's time for a new battery.

Also, one thing I do after EVERY iOS update is Force Restart my iPhone. I have never ever had any battery drain issues after an update, likely because this procedure helps with that. Do this after every iOS update --> Force restart iPhone - Apple Support (CA)

Hello!

Updating to iOS 18.3.2 is unlikely to damage the health of your battery.

Please tap here to learn how to update your iPhone. 

👉 Updating/upgrading your iPhone 

If your iPhone won’t update, please see: If your iPhone or iPad won't update - Apple Support. 

👉 Updating iOS: common issues and solutions - Apple Community

Have a great day!

lobsterghost1 wrote:

Also, one thing I do after EVERY iOS update is Force Restart my iPhone. I have never ever had any battery drain issues after an update, likely because this procedure helps with that.

Any thoughts on why this might help? Very interesting idea…