Unless you are billed monthly, the credit you have is not a true credit. The payments you have made will be going towards your next bill. For example we are billed 6 monthly and received our bills last week for those 6 months. The credits we had on both fuels then paid the bills. Ordinarily there is little, if any monies left in credit. When we received the last bill 6 months ago, there was in fact a small debt on the gas account.
We pay a lot less than you in a modest 4 bedroomed bungalow for two of us who are home most of the time. We are on the standard variable rate. You don’t mention if you are on as price fix or SVR so if you are on a cheap fix, your usage will be higher than if you are on a cheaper fix.
Our heating is on constant from morning until bedtime, currently at 18 degrees. At the moment the boiler is only firing up for no more than 45 mins during the course of the day. That will increase as we get into deep winter. We do have the advantage of being well insulated, so after the initial heating on a morning, the house is retaining heat during the day.
If you have an electric shower they can really use some energy. A bath or shorter shower is likely to be cheaper. Our shower runs off gas which is cheaper than electric.
Given the weather I use the tumble dryer most of the time other than for delicates. I can save some usage by washing slightly less. Not so easy with a young family. But if you can make things last a little longer before washing you can reduce costs. E.g. I used to wash bedding without fail every 7 days. I now wash nearer every 10 days. Does every item of clothing need to be washed after wearing once (some yes, but not everything). There are lots of things that we do out of habit rather than because it needs doing.
I have an electric oven and use the top oven where possible rather than the main oven, I also use a multi cooker which also air fry’s. That wasn’t bought as a cost saving measure, but it has reduced our energy consumption.
I will not be using an oil filled rad this winter, which will save us a lot of money over the winter months.
LED light bulbs are essential. We have had them for a number of years, although our outside light still has the normal light bulbs. However it is seldom used, so I will wait until those bulbs go before replacing them as it will cost more to replace them than I will save by buying new bulbs. If money is tight focus on replacing bulbs with LEDs for the bulbs that are used the most.
I have made lots of little changes, which have not impacted on our comfort, but have reduced our consumption by around half for electric. Gas has reduced as well, but the weather has been on our side. However it looks like some savings have been made by reducing the temperature on the thermostat from 20 to 18. It won’t be until we get to the other side of winter that I will know how much we have managed to reduce gas consumption.