My phone says my battery is to low for the phone to be able to update itself. I have around 34% left. How much is needed for it to update? 50%? I'm trying to update to Windows 10 Insider Preview for phones from Windows Phone 8.1.

  • 1
    I just started installing the latest build on my device which is already on W10 preview. My phone was completely empty when I started downloading it, the Installation process commenced when the battery level was at around 20% (phone is still charging while installing). Seems like this might be a different threshold for WP8.1.
    – Thomas
    May 14, 2015 at 23:16
  • Was able to install GDR2 or whatever (the update that updates the settings screen for 930) with 20% left. I had to charge up to 40% to be able to update to W10 from 8.1 on my 930. May 15, 2015 at 5:11
  • I guess it depends on the type of update - the W10 update probably takes longer so it needs more battery.
    – Thomas
    May 15, 2015 at 7:49
  • Hopefully in case of update can try with minimum 60% on battery so that it wont cause any crash.
    – vembutech
    May 15, 2015 at 17:29
  • According to Microsoft you have to charge your phone at least at 40% to install any update.
    – user16677
    Dec 8, 2016 at 23:54

1 Answer 1


I advise you to plug your phone to a charger and then begin with update. During update to W10 battery percentage can go wild (my Lumia 520 went from 90% to 10% during update, and after update it had around 40% battery) or it can get stuck on last(or any other) step for a long time.

Play it safe - plug it in and do not worry about the battery.

P.S. When I was updating my Ativ S from WP8.0 to WP8.1 it wouldn't update if I had less than 50%,

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