IOS 27 battery drain issue

To try to stop the rapid battery drain I put my iPhone 15 Pro in low power mode. The battery reduced 12% in two hours. Low power mode helped a lot.

Hi,

I’m experiencing a serious battery drain and overheating issue after updating my MacBook Pro to macOS 27.

My MacBook Pro is practically new — I purchased it about two months ago — and before the update, the battery performance was excellent.

Since installing macOS 27, the behavior has changed dramatically. For example, if I leave the MacBook unplugged overnight, even without actively using it, I wake up in the morning and the battery is completely drained. The MacBook also becomes noticeably warm or hot while it is not being used.

This never happened before the update. Previously, the MacBook could remain unplugged overnight with very little battery loss.

I’m very concerned because the device is almost new, and this issue started only after installing macOS 27. Please investigate whether this is a known issue with the latest update and advise on how it can be resolved.

[Edited by Moderator]

Yup even my 17 pro max is draining really bad since updating to ios 27. I even got the message stating that “your iPhone has been used more than usual since upgrading ios, and this may affect battery life”.

i hope this gets rectified before the battery life actually goes bad.

The same for me.

I upgraded to iOS 27 last night; my 15 Pro still has a decently healthy battery which usually lasts all day, charged at 100% starting my day at 6 am, to ~10% at around 11 pm.

Today it’s 3:09 pm and already down at 24%

I have been around for plenty of iOS updates, and I understand a new update is not going to be perfect right off the bat. However, after only 1 1/2 hours of use I'm down almost 40% this morning. I realize this will probably get patched in a future update but the sooner the better, I don't make it through the day any longer without having to charge my phone. My capacity is at 88%, which isn't bad. So, I want to submit my info to try and get a fix for this going asap. My phone finished indexing last week and it hasn't improved the battery life in several days since. It's about the same.

maverick_spartan wrote:

Insane battery drain for my iOS 13 pro.

This is most of all the updates till date.

It’s amazing. I have seen posts almost identical to yours after every update in the past 19 years.

As you haven’t defined “insane battery drain” there’s nothing anyone can say about it. To me “insane battery drain” would mean that the battery is dead one hour after it is fully charged. Is that happening to you?

If you charge the phone overnight with Optimized Charging enabled (a Best Practice) it should not require charging during the day, until the next overnight charging. If it meets this standard then the iPhone is working as designed.

Hello, I recently updated my iPhone to iOS 27 last week, and since the update, I have been experiencing unusually high battery drain. The battery is draining much faster than it did before the update.

Could you please check my iPhone and advise whether this is a software-related issue or if there is any problem with the battery? 

Same. Battery drain is really bad after upgrading my iPhone 15 Pro to iOS 27.

My attempts to fix

• Turned off Siri AI
• Connected to wifi for the day
• When outside kept close to a mobile phone tower at a festival so my iPhone 15 Pro had full connectivity

Battery drain is still really bad.

It is terrible what they did in iPadOS 27, my Pro M2 is draining battery alone with no apps in background and either in flight mode. Optimization finished several days ago.

My battery was lasting days and now cannot get 24 hours without charging.

TE RRI BLE

I’ve been on a holiday on phone all day chilling in the sun max brightness 16 pro max and battery usually between 30-40% with 77% battery health update last night and battery is shocking I’ve had to come in and charge phone was at 20% 3-4hrs before I have been before update yesterday

I tried doing the force restart and gave it some time to see if it improved. My battery life is still rough. My phone was in the red by 12. I charged it and it still didn’t last me through the rest of the evening.

Did you open a support ticket with Apple about your 15 Pro battery drain issue?

I haven't had time to do that yet. There's very clearly an iOS 27 battery issue happening with my 15 Pro Max that did not exist with iOS 26.

I'm having the same issue with my iPhone 17 pro since i have updated to iOS 27. My biggest concern is my phone keep getting Heating even after fully shutdown 😕😕

First 2 days after updating went without an issue. No battery drain, No Heating

But after those 2 days my phone began to heat and drain battery like crazy 😕

I have waited for the iOS 27.0.1 hoping that it would fix the issue. But it didn't either... 😕

I have tried:

1. Factory data reset

2. Turning off siri beta

3. Fresh install iOS via restoring using my MacBook pro

Nothing fixed it yet...

*Only after Turning off wifi completely drops the heat by some amount

My biggest concern is how iPhone keeps getting Heating when it is powered off?? I shutdown my phone before 6 hours of sleeping. Then after waking up i grabbed my phone and noticed it is getting hot even when fully powered off (not powered on yet).

Then after powering my phone on i realized that more than 30% of battery drained during night even when phone was fully shutdown 😕😕

My phone is only just 6 months old. I have another 6 months of apple care warranty. But I'm fron sri lanka we don't have apple stores here. I imported this phone through a reseller by paying 2X the value of the phone

My phone has never dropped. No damages. And no water damages.

I don't know why this happens to my phone 😕

I hope apple will fix my phone with upcoming ios 27.2 🥺 otherwise i will have to ship my phone back to japan and claim apple care warranty. And the process will take about 2 months 😞

After 27.1 update my battery drain one present in every 40 to 50 sec my I phone 13 battery drain so fast please apple fix this before update my iPhone battery working 10 12 hours heavy use please apple fix this as soon as possible

same here. after updating to ios 27 last week, the battery drain is insane. hope this gets fixed by the next update. thank you