Have I been silly.

magyar

It's worth reiterating that when you pay Direct Debits to a utility you are not 'paying your bill'. You are simply giving them money that they will use to pay your bill (usually quarterly or six-monthly).

If they take £30 a month and it's too much then you'll get it back at the end. Likewise if you're not paying enough then you need to pay some more.

My advice is that roughtly once every two months or so, phone up your gas company and give them a meter reading. Their billing system will therefore be more accurate.