E.ON, Scottish Power, British Gas and SSE websites have crashed, according to customers attempting to submit their meter reading.
A message on the British Gas website told customers it was facing "some technical issues we're trying to resolve as quickly as possible". The message said customers could still submit readings but warned it could take "a little time to update your account with the meter reading you provided today".
EDF Energy's website also reported problems, apparently as many people tried to submit their meter readings on their account. The main page of EDF Energy was working, but when customers clicked through to the MyAccount page they were unable to log in.
