Would never, ever recommend OVO Energy. We had a direct debit which they kept automatically updating. It was the same for about a year, and almost as soon as we cashed in the +£100 we were in credit, they increased our direct debit from £75 to £120. We managed to battle them back down to £90 but still thought it was an enormous price change given that our usage levels were only ever so slightly higher than the previous year. They refused to see eye to eye with us and then left us with a bill of almost £200 at the end of our time, and refused to let us switch without paying it in full. Absolutely astounded that as a customer who'd paid on time by DD every month, they could treat so badly. Never, ever use OVO Energy.