British Gas Business has agreed to pay £9.5 million for failing to handle customer registrations, complaints and billings.
According to Ofgem, tens of thousands of business customers were left with delayed and inaccurate bills when the Big Six company implemented a new IT system worth £40 million in 2014.
More than 6,000 new business customers also experienced delays when registering with the supplier, which resulted in a significant increase in the number of complaints.
The regulator says many were handled “poorly or not on time”.
British Gas Business however went to Ofgem voluntarily to report the problems in December 2014.
Ofgem said the energy company has since improved its service, hired up to 350 specialist agents to handle increased calls and a backlog of complaints.
British Gas Business will pay affected micro business customers and give the rest of the cash to charity Money Advice Trust, which provides the Business Debtline service, to help consumers in need.
Dermot Nolan, CEO of Ofgem said: “British Gas Business has done the right thing by coming forward to Ofgem to report problems with its new IT billing system and has since worked hard to improve its customer service. However, British Gas Business’ implementation did go wrong and it didn’t act quickly enough to put things right.
“Ofgem welcomes suppliers investing in new systems and recognises that this can be challenging. However the £9.5 million payment also sends a strong reminder to all energy companies that they must treat consumers fairly at all times, including while new systems are put in place.”
The energy company claims complaints fell by almost a third in 2016 compared to the year before.
Gab Barbaro, Managing Director of British Gas Business, added the new IT system combined nearly 100 different systems into one and didn’t go as smoothly as expected.
He said: “We’ve worked hard to put this right since and Ofgem has acknowledged this today. We’ve restored a very good quality of customer service and more and more of our customers are going online to use the new billing system. I’d like to apologise to our business customers for any inconvenience caused when we were implementing the system.”
Last month the Big Six supplier agreed to pay £4.5 million for failing to deliver advanced meters to some larger business customers.