Could be many different things that's causing this.
One thing that many do forget about and that don't show up in the battery drain stats is device maintenance but also network issues/comms that could cause battery drain (BT, Wifi, Cellular, Ux chip etc)
Chat GPT summed some of it up pretty well below.
When other devices on your Wi-Fi or Bluetooth network "talk" to your iPhone, it forces the phone’s antennas to stay awake and process data, preventing it from entering a deep sleep. This constant background chatter drains the battery rapidly. [
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How to Stop the Network Drain
1. Turn on "Low Data Mode" for your Wi-Fi
When a network is marked as low-data, your iPhone stops background tasks like automatic app updates and cloud syncing. [
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- Go to Settings > Wi-Fi.
- Tap the "i" icon next to your connected network.
- Turn on Low Data Mode.
2. Turn off Local Network Access for specific apps
Some apps constantly scan your local network for other devices (printers, Chromecasts, smart TVs, or other phones), which causes massive battery drain. [
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- Go to Settings > Privacy & Security > Local Network.
- Review the list of apps and toggle off any third-party apps, games, or social media that don't need to communicate with devices on your Wi-Fi.
3. Turn off "Calls on Other Devices"
If you have a Mac, iPad, or another Apple device nearby, your iPhone constantly communicates with them to sync phone calls.
- Go to Settings > Phone > Calls on Other Devices.
- Turn off Allow Calls on Other Devices (or toggle off the specific devices you don't need).
4. Reset Network Settings
If a software glitch is causing a loop of background data packets, clearing the network cache will resolve it. [
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- Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. (Note: This will erase your saved Wi-Fi passwords).
To help narrow down the exact cause of the drain, could you tell me:
- Which apps are at the top of your Battery usage list in Settings > Battery?
- Does the battery drain faster when you are connected to Wi-Fi at home, or when you are out on cellular data?
