British Gas, EDF Energy, Npower, Scottish Power, First Utility, Good Energy and Opus will introduce the limit by the end of 2013 or “as soon as is practicably possible in 2014”, the regulator said. Eon and SSE have already set such a limit.
Back billing accounts for an estimated £178 million or 3 per cent of the total value of bills for small and medium enterprises.
The voluntary commitment builds on regulation Ofgem is bringing in to enforce standards of conduct for energy suppliers and make them provide better information.
Philip Cullum, consumer partner at Ofgem, said: “We want to give businesses more protection in the energy market. That’s why we have put in place reforms to ensure businesses get fair treatment from suppliers and clear information on when they can shop around for better deals.
“Small businesses have told us they’re worried about facing big energy bills out of the blue, and our latest data reveals that suppliers’ record on so-called ‘back-billing’ is poor but moving in the right direction.”
“Our reforms place a general duty on suppliers to treat smaller businesses fairly in a range of key areas, including back-billing. But we also wanted more specific commitments on limiting back-billing so we welcome the new arrangements announced today.”