Watch OS 7.3 causing battery drain on iPhone XS

[ahmede]

I have noticed battery drain on my iPhone XS running iOS 14.4 and Watch OS 7.3.

My phone battery lasts much Longer when not connected to my Watch 4 ,

Overnight drain is clearly noticeable on my phone when connected to my watch

Battery life on the watch 4 is not great either.

 

[iPhonNick]

I'm using an iPhone XS and AW Series 4 too. Both with the latest update, but I'm not seeing battery drain issues (both do last 2 full days without recharge).
Try unpair/re-pair the Watch and give it a few days to stabilize itself?