Confusion with est price on comparison websites

oxymore

I am currently with EON on their standard EnergyOnline tariff which charges 25p for electricity (up to 900 kWhs/yr then 9.45p) and 6.5p for gas (up to 2680 kWhs/r then 3.16p). I have used 3177 units of electricity and 1451 units of gas in the past year. After entering this on uSwitch and Moneysupermarket, it tells me I only spend £500 in total whereas my bill for that year was actually £1000! This was the actual amount they've debited from my account after I pay standing order every month. Could anyone explain how these estimates work? Should I double the predicted price the website gives me for all the other suppliers in this case?

notbritishgas

See my reply on your other identical post!!