Its almost impossible for a customer to correctly work out bills themselves (hence why the pricing/tariffs should be more straight forward) it's due to the fact that you don't know the calorific values of the energy supplied needed to work out bills. Each area of the UK is different. I'm trained to use it but it still baffles me. Of course I can use the systems to calculate a bill but still knowing what I know, I wouldn't be able to it manually.
Someone mentioned that if they went "dual fuel" then they would save. For most companies you are correct, the policy for mine was if you take DF and pay thru D/D for 12 consecutive months then you will receive £100 bonus at the end of it...however miss one payment and you won't get it. Also the Tariff for dual fuel is standard...there are better ones to be had if you sign online. There is also tariffs and plans to help vulnerable customers such as with a disability, speak to your suppliers people.
Its a fact that a high % of the population will be in fuel poverty very soon, lots already are :(
Like I already stated, unless you are elderly/disabled and the energy company have this in the system then the responsibility to read the meters is YOURS. Companies, by law, must read/check them once every 2 years. An easier option so that you don't have to keep ringing them in is to sign up for the online service, the company will E-mail you when it wants a read or you can enter when you choose to, like monthly if you wish.
Its easy to build up a high bill if you are not providing reads every 3 months, if say 2 of your quarterly bills were estimated below what you used by £150..... When the energy company finally did get an actual read from the customer you would have £300 for starters then what else you had actually used on top....its not worth leaving it.
And yes some one else mentioned if you are a customer who hasn't had a meter guy out for well OVER 2 years- then the back bill policy can apply, however if a customer could have provided a read (i.e no disability, not recorded on the system as needing the engineer to visit) then it will be very hard to get them to apply it, but you could still ask.
SKIPTHELIGHTFANJANGO - Is that each? If its for both then I would seriously get in touch with BG with reads and get them to verify that you pay enough, so you're not given a big bill later. I've had customers paying double that for the same sized properties, but it depends on how many live there, if you heat all rooms or just the ones you actually use.
Dolallylass - You have it sorted now, Don't worry about how the money is distributed just provide regular reads still so that if you do use more, its caught early and your payment might just need adjusting by a few pounds each month to cover it. Also I'm not saying that you will, but be careful about defaulting the monthly plan as often the energy companies aren't so forgiving that after they stretch terms for repayments they get defaulted and they won't put you back on the same plan as before. If, E.g its your bank at fault then you can provide proof of that and they will help you and quite often set it straight back up again. ALL energy companies are cracking down on the debt thats owed to them, so the rules can be quite harsh sometimes, but if you genuinely need help it's available.