Ofgem allows Npower to continue telephone sales
Npower, the most complained-about energy firm, has been told by the regulator that it will be allowed to continue with telephone sales.
It follows improvements in the company's customer service standards, and fewer late bills being sent out.
The energy regulator, Ofgem, had threatened to stop Npower selling contracts on the phone, unless things improved by the end of August.
Npower said it would continue to make further improvements.
The number of late bills being sent out by the company fell to 62,000 in August - compared to 280,000 in June.
The target set by Ofgem was 100,000.
The number of complaints received by Npower fell to 99,799 in August, compared to 120,016 in June.
Npower has received more complaints than any other energy firm in every quarter since October 2012, according to figures compiled by Citizens Advice.
Sarah Harrison, Ofgem's senior partner for enforcement, said she was encouraged by the improvement.
"But this is only a first step to turning round their customer service and billing performance," she said.
"We will monitor their progress and continue our investigation into the reasons why Npower's problems occurred."
Roger Hattam, Npower's domestic retail director, said 98% of customers were now being billed on time.
"However, the journey doesn't stop here as we're working hard to make even more improvements," he said.
Npower has blamed its problems on a new computer system.
And it has taken on extra staff to try and improve its performance.