watchOS 9 battery drain

Hi here, I have been encountering the exact same problem for 2 weeks but have finally found a way that stops the battery drain for me.

I'm using Apple Watch Ultra but started encountering a serious battery drain issue starting from last week, battery evaporates at a 10% hourly rate on idle state even when my low power mode is on. Some solutions would suggest repairing or factory reset, but none of those actually worked for me. I had to use my AppleCare for an exchange, but the second watch suffers from the same nightmare.

After reading: apple.com/uk/batteries/maximizing-performance/

Disabling Bluetooth on your iPhone increases the battery drain on your Apple Watch. For more power-efficient communication between the devices, keep Bluetooth enabled on iPhone.

I noticed that as long as I keep the bluetooth of my iPhone on, the battery situation will be normal. (now at ~1% per hour instead of 10%)

Personally I feel that there is a problem with WatchOS 9.1 when dealing with the no-bluetooth situation, but I'd suggest to give this a try if you are suffering from the same issue & also have a habit to keep the iPhone bluetooth disabled.

Hope this helps somebody.

+1 for unpairing and re-pairing to resolve the issue. After the OS 9 upgrade, I immediately went from 15-16 hours of battery life to 10 on my Watch 6. Battery health was 90%, so it was not an old battery issue. Unpaired, re-paired, restored from a backup, and I'm right back to my old battery life and possibly even a little better.

I also turned off a half dozen or so little-used Watch apps, in case the problem was that one of them had a compatibility issue. And I changed my watch face to something with fewer complications (California), just in case that was part of the problem. But this afternoon I moved back to the Infograph face and am not seeing any noticeable drain increase as a result.

Thanks. I also have a mesh system at home and a couple of other folks in here suggesting the possible root source had suggested it was wifi-related. Yesterday AM, after another drop to <80% by the time I left my house in the AM, I turned off wifi on the watch and only used the cellular option. I also turned off cellular data for a number of apps in case those were driving the behavior. My watch was <20% by 9:30PM, but that was still significantly better than I've experienced since the 9.2 update in December. Today, even better. Without wifi, my watch is at 72% at 3PM. Compare that with fully depleted by 2PM on Wednesday.

In short - you're on to something with the wifi troubleshooting!

Since I posted this a week ago, I followed others' troubleshooting guidance and turned off the wifi (I have a wifi+cellular Series 4). That seems to have done the trick.

For more detail, I also had deleted a few apps that I wasn't using in case one of them was driving the drain, and I turned off cellular data for all but a handful of the apps. For the first time in over a month, I was able to use my watch all day again, where during the glitch period beginning with the release of 9.2, the battery would be dead within about 4 hours.

Since then, I've turned cellular data back on for most and continue to get a full day's use out of the watch and features. It's now been on my wrist for 16 hours and I'm at a 48% charge. Tomorrow, I'll turn the wifi back on and report my results at the end of the day.

Tried unpair ing a d actually restored from an iCloud pre-OS9 backup. However, on completion I was still on OS9 ☹️ and didn't solve the problem.

Mine was solved by changing my watch face from Unity Lights to a Chronograph Pro one.

Confirmed that it’s definitely a cellular issue for me. I have now had two lengthy runs with my cellular turned off listening to Pandora (offline) via Bluetooth while using the workoutdoors fitness tracker. I do not get the extreme battery drain that I experienced with cellular turned on.

Some more observations....

1. I have seen that the battery drain does not happen if I am away from home and not connected to my wifi network.
2. When I am home, the wifi connection seems to drop (if I go into the wifi settings, I don't see a connected network) or sometimes, the watch will be connected to a different SSID than my phone (I have multiple SSIDs being published by my routers/access points - the routers are in "bridge"mode). In both cases, I have noticed that the battery drains rapidly.
3. If I manually switch my Apple Watch to the primary network that my phone is connected to, I don't see the battery drain.

There appears to be no rhyme or reason why the watch is switching or losing the wifi the network. It will be connected to the primary SSID when I put it on the charger at night and in the morning it will be connected to a different SSID (the watch will also be pretty warm when I take it off the charger). Anyone else seeing this?

You should be able to fix the issue by unpairing your watch from the phone and then pairing it again. I had neglected to do that after someone suggested it, so I did that the other day and now my watch’s battery use is back to normal again, lasting over 24 hours.

>You should be able to fix the issue by unpairing your watch from the phone and then pairing it again.

I have done that multiple times and it does not work for me. The only thing that seems to work is restarting the watch and making sure that it is actually connected to a wifi network. If it is not, I manually select the network. For some reason, the Apple Watch will not automatically connect to wifi (at least in my case) and the battery drains rapidly. If I restart it and select the network, it will act normally. Thought it does drop the network periodically and I have to restart the watch and reselect the network. I did this twice yesterday and by the end of day, my watch was at 54% with no charging during the day.

To confirm if the wifi network is actually selected, I swipe up from the control center and hold+press the wifi icon. The wifi icon is typically "blue" (wifi is on), but after the network details come up, it shows that no wifi network is selected. On my wife's Series 3 (WatchOS 8), the wifi selection is automatic.

Not sure if this is the root cause, but it seems to work for me.🤷🏻

Updating to watchOS 9 means you have updated to the initial version of watchOS 9. Make sure you have updated to the latest version (same goes for iOS or any other OS). The first versions of any Apple OS have gotten more stable but some bugs may still not be found and fixed before the release. Therefore, either wait for X.1 or X.2 release before updating or make sure you have updated to the latest version whenever you have an issue.

If you are already on the latest version, then it's a little bit more difficult to say. You could try and see if you have any weather-related widgets on your watch faces and remove them and see if the battery situation persists. 🤔

@AScottGoodwin - the only way I have found to fix this is to periodically go in and check if the watch is connected to wifi. If not, I manually select it and things go back to normal.... for a while, until it loses the connection again. What is really strange is that if I am away from home, the watch behaves normally. The only thing I can figure out is that it may have something to do with my wifi setup.

I have a mesh system and I broadcast multiple SSIDs from the different mesh points (with one common dual band SSID published by each mesh point). I have noticed that if I move from room to room, the watch will sometimes drop the connection and I have to manually reconnect. An apple support rep told me to turn the setting for "Auto Hotspot Settings" to "automatic" but I don't think that did anything (I was very skeptical that it would do anything and I tried to tell him that I DON'T want this watch to join my cellular hotspot, but he was very insistent). I have turned back to "Ask to join" again.

Apple has replaced my watch under AppleCare because of this issue but obviously, the replacement has the same issue and no one at Apple seems to acknowledge this.

I think I've finally found a solution that seems to work (at least in my case). Prior to taking the steps below, my watch would need to be charged at least twice a day.

After trying 3 different watches, setting the watch up from scratch multiple times. resetting the network settings on my iPhone, trying low power mode etc., I finally took the drastic step of completely erasing the phone and setting it up as new (did not restore from backup). So far (it's day 3), my watch has had about 65% battery at the end of the day (off charger around 5:30 AM, on charger 9:30 PM). I have an iPhone SE (2020) and AppleWatch Series 8 (non-cellular). I had the same issue with my AppleWatch Series 4 after upgrading to WatchOS 9 (that watch was traded in - which I feel silly about now).

I took screenshots of my iPhone setup before I wiped it. That made the process somewhat easier but I still missed some items/settings and am tweaking them as I find out. My phone was enrolled in my work device management but given the size of the organization (thousands of employees), if this was caused by the MDM software, there would have been other complaints. However, when I reset the phone, I did not re-enroll it, so I am not sure if that had any impact.

The one issue that I still seem to have is that the watch will sometimes not reconnect to my wifi network. I have disabled private network on both my watch and my phone but it has happened after that a couple of times. It also seems to happen if I leave and am out of range from my wifi network - the watch will sometimes not reconnect when I return and I have to connect it manually. I have now been checking if the watch is connected to wifi first thing in the morning, when I come back home or when the watch fails to unlock my Mac (get a message wifi signal too weak).

After 3 different watches, many trips to the Apple Store and multiple phone calls with Apple Support (escalated to 3 levels up), I was ready to give up on the watch. Jury is still out, but hopefully, this may have solved the issue. Hope this helps someone.

As I mentioned earlier I changed my series 5 watch face from Unity Lights to Chronograph Pro and it is now fine and doesn't freeze now and battery life is back to where it was pre OS9.

See my previous comments on this. Until Apple provide a solution try changing the watch face. I use to have Unity Lights as mine. Series 5 watch upgraded to OS9 and battery drained, but also the watch would "freeze". I now use a Chronograph Pro face and all is back to normal.

This is an issue I noticed immediately after upgrading my Apple Watch 4 (battery health at 94%) to Watch OS 9. Without particularly using the watch, it drops at the rate between 10% per hour to 1% per 2 minutes. But there are also good days when it drains just as Watch OS 8. I've done quite a few tests without a proper profiling tool and here are some findings:

1. There are bad days and good days. Good days would be like running Watch OS 8, draining batter like before. No need for Low Power mode.
2. It's not related to hardware that we have control of: Wifi, BT, Cellular Data, etc. These don't impact the battery drain issue
3. It's not related to Watch Face. In particular, the Noise complication isn't the major cause of the issue. Other complications afaik don't read any sensors and should consume less energy. I haven't looked into data refresh model of watch complications development but my guess is there's an interval for data refresh. Drawing the complications won't consume much energy either. I've tested a wide range of watch faces including watch faces without complications, still drain like crazy.
4. Heart Rate Monitor draws energy, but it doesn't look like it takes more in Watch OS 9 than 8. The plotting looks the same as before.
5. Heating up. Watch becomes warmer than usual, and the temperature difference is noticeable. This is usually a sign of CPU utilization. Without a profiler, I can't really say what is running but this seems to be the major cause.
6. Low Power mode helps, most of the time. Apparently, the mode disables the heart rate monitor, it also reduces background app refresh, according to Apple, "Background app refresh happens less frequently". Whatever process Low Power mode shuts down would be the root cause for the battery drain issue. However, I also noticed that if the music control is up (when you are listening to music on your phone), you get a chance of screwing it up again, even in Low Power mode.

Work around of the issue:

1. Turn Low Power mode on, let it run for a while and turn it off, hoping the processes that were shut down don't start.
2. Pray it's a good day
3. Bring a charger.
4. Unpair and re-pair. I haven't tried myself but I guess it might help.