Really depends on the insulation if you're in Western Europe close to the sea (making the winters less harsh). I live in a flat and the whole complex has been upgraded with modern insulation and modern windows about five years ago. I turn on the heat on a few days when I feel exceptionally cold, otherwise I don't and it still maintains 18-19° (being chubby helps, that's my comfort temperature). It's not because my neighbors are doing the heating for me -- I've talked to them, and they barely ever turn it up, either.

Granted, that would change somewhat if we get a super harsh winter here, but otherwise: I consume much more electrical power than heating.