But the current bill covers Aug/Sept/Oct when it was mostly quite warm & still quite light so nearly £400 does sound really dodgy, even for a cremolatorium in NI.
We have gas heat & gas hob - everything else is leccy - our monthly DD is £71 & our usage really doesn't vary much between summer & winter (cos computer use is the same all year round, LOL)
Have they done a catch-up meter reading?