I have to chime in here too! I was consistently getting around 8 hrs 30 mins or so on my SP3 with about 30% left. But after the last firmware update something happened. Now, after 4 hrs 30 mins, the system reports a battery level of 46%!!! My work pattern has not changed - OneDrive, Word, very little browsing, most notifications off. I have drained the battery and have charged back up to recalibrate. Any ideas? Edit: I have the i5, 4GB RAM, 128GB version. Edit 2: I just ran the battery report and I notice that from the 21rd of Jan, this year, the battery performance dropped from 8 hr 25 mins to 5 hr 40 mins (as on the 26th of Jan). It could be that I am not reading the report correctly, but this seemingly bears out my experience in my daily usage. Edit 3: I just reduced the screen brightness - on battery - down from 40% to 38%. Let's see if this makes even an iota of difference.