iPhone 7+ drops to 1% overnight

Have you ever had your battery replaced? How long have you had your iPhone 7+? Although the device is relatively old release wise I know some places offer them still as new phones (often carriers offer them as a free option) so it’s hard to determine if your particular battery is old. Also what is your battery health percentage? If it’s below 80% it’s time to replace it.

Protect & Prolong life of your iPhone's Battery:

1. About the battery usage on your iPhone, iPad, and iPod touch ...
2. Batteries - Maximising Performance - Apple (IN)
3. iPhone Battery and Performance

Try some of these options too.

1. Avoid Screen Mirroring
2. Put on Low Power Mode
3. Put Auto Lock On (1 min):- with low power mode it will be 30 Sec
4. Put Auto Answer Off
5. Disable Push notifications for apps you do not use often
6. Keep your iPhone Face down to prevent notifications to light up screen
7. Enable Auto Brightness:- Settings > General > Accessibility > Display Accommodations > Auto-Brightness [Enable]
8. Manually lower brightness from Control Center
9. If you Want to watch continuous Video. Stream it on TV or a Monitor
10. Don't force close apps; Apps which are not on frontend screen are paused by the system to save energy. Apps require more energy to re-launch. Apps which are open in the background use large memory is a myth and quitting them is counterproductive
11. Location services to be allowed only while using the app
12. Set your iPhone to fetch email and calendar data from internet less frequently
13. Turning off Background App Refresh 
14. Charge before it drops below 20-30%
15. Try connecting to trusted Wifi where ever available in stead of Cellular
16. Enable Airplane mode in areas with bad cellular and wifi coverage. Your phone keeps trying for reconnection with the missing / weak network. This uses lot of energy
17. Switch off Wifi & Bluetooth while in Roaming or Not in Range
18. Enable "Wifi Assist" : Settings > Cellular or Settings > Mobile Data > Wi-Fi Assist [Enable]
19. Periodically Check your Battery Health (Settings > Battery > Battery Health)

Hi, I'm having the same issue. I also have a 7+ and, when I go to sleep, its power percentage is generally around 40 - 80%. In the morning, the percentage shows 1%.

• Rebooting brings the percentage up to the proper amount. For instance: I went to bed last night at 61%. Woke up at 1%. Rebooted and it was up to 59%.
• This has happened several days in a row.
• Right now, based on some suggestions I found elsewhere, I'm planning to run my phone down completely and hope that a reboot from less than 1% will trigger some fix.

Other than that, I have no idea. But I'm following this thread to see if anyone else can suggest a fix.

It is good that this is a known issue.

One thing you may have done is accidentally fallen for a scam, and made you download files that drain you’re battery.

Have you gotten any suspicious emails?

This link can help: https://support.apple.com/en-us/HT204759

Well, if they have you’re number or email address, because they are texting you, maybe report the scammers number or email address to Apple.

The email address I would recommend to report to Apple is reportphishing@apple.com

This is a nice list of things to do to protect a phone's battery in general but it doesn't answer the specific question.

I have gotten a *lot* of suspicious texts in recent weeks. I don't ever click on links in texts, though. Could simply opening the text (which I did in order to block) have compromised me?

No...not of my understanding. What were the texts? Phony virus scams?

Yeah. "Let us know where to ship your gift, click here..." sort of stuff. Obvious scammy stuff.

If a battery is depleted, would the "Battery health" percentage reflect that? My battery health is still at 81%.

Your battery is probably depleted, the 7+ is now an older iPhone model. Have the battery replaced.