<sod >For a typical household on dual fuel, that means that the average annual bill will increase by 7.3 per cent or Â£76.Â  Chief executive Mark Hodges said that British Gas had last raised prices in November 2013.< eod>< sod > For a typical household on dual fuel, the average annual bill will therefore increase by 7.3 per cent or Â£76, affecting over 3 million customers.< eod>