The consumption of a boiler or heaters is calculated based on 210 days of the year. Your electricity bill is estimated for 365 days of the year. Hence it’s important that you do not estimate your heating costs by 1 or 2 days of consumption. It’s always the case, when you first turn on your heating the first few days of consumption will be higher and it will go on to decrease. That applies to all forms of heating as it has to warm the fabric of your home. After that with reasonable insulation, you only have to consume based on the heat loss, temperature to be maintained and the hours of comfort heating your program. For this reason, every user profile and property will be different.
So please remember this about running costs when you start your heating for the season.
Electric heating is considered 100% efficient (at the point of use), however, electricity is more expensive than gas and oil. To reduce running costs, you must insulate your home to a higher standard, switch to the best tariff that meets your user profile, programme your heating for the hours you need, and set only the temperature you require.