iPhone 17 battery drains quickly with normal use

I bought the iPhone 17, upgrading from

the 14 and noticed that the battery wasn’t performing any better than my

old phone which has 76% battery health! I was also receiving a message saying the battery couldn’t be authenticated which Apple said was a firmware issue. After resetting my phone the error message did resolve but the usage did not. I decided to return the device and got a new one (from the same shop) and received the exact same battery warning. I’ve now returned both devices. I lost 20% in a 45 minute gym session only using my Spotify in the background and a workout app. Apple support suggested I turned low power mode on after charging! It’s an £800 what do

you mean!!!

Correct. NOT using either 80% charge or Optimized charging will damage the battery, but slowly.

Leaving it plugged in overnight with either option will extend the life of the battery, because the “housekeeping” tasks that run at night as well as incoming texts, email, notifications and app data updates will use mains power instead of battery power, allowing the battery to rest.

It also has the added advantage that you can turn on automatic backups and it will back up your content every night.

Dude. It’s obviously not an after update issue or the phone being new and trying to index everything. I’ve had this phone for a month now and this dumb phone only lasts me 8 hours before getting below 20%, average usage btw, not more than 4 hours of screen on time. This isn’t a restoring with backup, resetting, force restarting type of issue. 100% of battery health on my iPhone 17 should last over the advertised “30 hours of video playback” before it dies. Not 8 hours with only half of that being with the screen on and not doing much but scrolling on social media and some YouTube. Battery saver doesn’t even help the issue there being about the same results. This is a joke.

I previously owned a iPhone 11 and even after 5 years the phone usually dropped between 1-2 percent of its battery. I’ve also seen no drop in battery multiple times even when I left it unplugged in the night. I’ve been using a new iPhone 17 pro since the last 6 months and idk why but it usually drops between 6-7 percent in the same use case and same apps and same screen time. I will agree though that it does last longer and I usually charge it after evey 1.5 days. But I don’t like this battery drop in the night or when the phone is resting. Also I keep my bag round app refresh off it helped in the iPhone 11 and I think it might help here too.

Just to set the record straight: Apple hawks the iPhone 17 with the claim "Up to 30 hours video playback". Anybody that sees that should be justified in expecting that they don't need to recharge their phone twice during the day just to keep using it. And I am not talking about Meta (no Social Media installed) or a temporary effect after an update - just day-in, day-out usage (texts, occasional phone calls, weather apps...) I follow all of your advice (plug in every night, charge to 100%, use smart power management etc.). It's true that a more powerful phone will use more battery, but the above is clearly misleading advertisement (even the 10 hours and 49 minutes you quote is a lot less than the claimed "30 hours video playback". At the least, maybe Apple can provide a setting that allows people to find the power-hogging apps (including the ones that use a lot of power in the background) and a throttle to keep them from doing that.

20% in 8 hours is pretty good, your phone is never idle. If it is out of your reach for the shift then turn on low power mode while in the car.

Same issue here. New iPhone 17 with all default settings. I’m only using 3 hours of WhatsApp and 1 hour of YouTube and I’m already at 20% battery left. So no camera, no gaming, nothing special. Brightness only 33%.

It’s very disappointing with a new phone.

I come from a 12 pro with 5 year old battery at 75% that performs even better.

I use the 17 and honestly, I am very disappointed with the battery life. I can hardly get five hours of screen on time before I need to charge. I also noticed standby battery draining, It’s not the best especially having used the 13 and 15 base models . I think it’s an issue with all versions, probably an update might just fix it .

Also, I have been using the phone since its launch date so this isn’t about me just transferring from an old device. It’s been almost 3 weeks and there’s been no sign of improvement.

Me too, very weird. My iPhone 17 Pro Max was manufactured on August 2025. Im starting to think its a hardware issue that the first patches of iphone set deal with.. We need a replacement for this trouble. Also, just by using Safari, my iphone becomes very warm.

Rebooting first stops all apps, which takes energy, then starting loads all apps, checks status and syncs with iCloud, mail, contacts, calendar events, notes and reminders. All of these steps use energy. 3% is not surprising. But the real question is WHY are you rebooting frequently. I never reboot, except to install an update.

I agree with Mac Jim ID. People dread the time when their battery health (capacity) hits 80% and they need a new battery.

Setting a charge limit to 80% has the same effect, except 2 years earlier.

Charge to 100% with Optimised Charging on, every night, all night, on Wifi

I’m just past my 14 day return window on my 17 Pro max. I can’t believe how quickly the battery drains with normal use. 100% after overnight charge, down to 50% within 5 hours. At the end of a normal work day, it’s down to 18%. I thought I would no longer have to bring portable charging with me. Sadly, not the case.

I’ve the exact same issue, battery drains quickly overnight by 10-15% I would charge 80% at night and in the morning it would be 70/65%.

I sent my phone to Apple repair center and they found nothing by keeping the phone for 2 days, after the iOS 26.1 update it’s still the same, called the support again and they found nothing and said they can’t help further, which is not a Apple reply, iPhone 17 pro max here.

Both phones were bought from Apple (online) and picked up at the official Apple Store in Watford. I was even told at one point during the 2 weeks I was struggling with this that the battery issue could be something I transferred from my old device during the iCloud back up so when I purchased the second device I set it up as a new phone without back up (which in itself is massively inconvenient - one key reason I buy into the Apple sphere is for its seamless integrations across devices). I was honestly just really disappointed with the experience I had with the 17 which is a shame cause aside from the battery it was really a great phone. At one point I thought perhaps I fell victim to a faulty batch of phones (cause what are the chances the same battery error shows up on 2 different devices) but reading through how many others have experienced near identical problems is disheartening. I had originally planned on waiting a week or so and repurchasing the same once again but I don’t know if I can face another failed iPhone set up!

I have had my iPhone 17 for 9 days and the battery cycle count is 9. This battery is horrible and I’m having to charge it multiple times a day. I did check the battery health of course it says normal but why is the battery capacity being used completely every single day? That’s not normal. I to am very very disappointed.