Npower lost almost 355,000 customer accounts in 2015, the firm has revealed, as it announced it is axing 2,400 jobs across the country.
Customer gas and electricity accounts dropped by around 7% to 4.77 million by the end of 2015 because of "over-complicated processes" and poor customer service.
Problems with its IT billing system saw npower issue more than 500,000 late bills between September 2013 and December 2014.
This, along with poor complaints handling landed the provider - owned by German energy group RWE - with a £26 million fine from regulator Ofgem.
Npower power said it is beginning to see improvements in its customer service, with complaints per 100,000 customers more than halving last year and coming in below the industry average in the fourth quarter.
Trade union Unison has called today's loss of 2,400 npower jobs "a devastating blow to the workforce" and said that staff are paying the price for mistakes in management.
Npower has been in trouble for some time thanks to poor decision-making at the very top, and workers are now paying the price.
The company's failure to invest properly in new systems has left it with one of the worst customer service records in the business.
Npower is axing 2,400 jobs over the next two years, here's who will be affected by the losses:
- An office in Burton, which employs around 200 staff, is confirmed for closure
- Some job cuts will take place in the Midlands, one of the firm's major operating areas
- Aside from Burton, the rest of the job losses are not "site specific"
- A mix of those who work directly and indirectly for npower will be axed
- There will be no job cuts at any of npower's power stations
Npower's chief executive has admitted that the firm's "overcomplicated procedures" have contributed to the loss of 2,400 jobs, as it was forced to outlay extra costs to "put things right" for unhappy customers.
Paul Coffey said that the energy giant lost sight of the "fundamentals" and called the firm's losses of £100 million "extremely disappointing."
They show a business that tried to do too much, too soon, while not focusing enough on the fundamentals in a constantly changing market.
This led to over-complicated processes and procedures resulting in unhappy customers, too many complaints and extra costs to put things right.
...Energy should be simple for our customers and we have complicated it.
...I regret that, as we simplify and streamline our activities, this will mean inevitable job losses but I am convinced that these steps are critical to protect the thousands of jobs that will remain."
Today's job cuts will affect a mix of employees who work directly and indirectly for npower, over the next two years.
Npower has said that axing 2,400 jobs today is part of a two-year recovery plan to cut costs after the energy giant suffered losses of £100 million in 2015.
The German-owned firm announced the cuts along with a four-point plan to deliver a "robust business":
- Lower costs: Make extensive cost savings to help return the company to profitability
- Simplify the business: Reduce, and in some cases stop, some of its energy services activities
- High-quality customer service: Including improvements to the billing system
- Looking to the future: Preparing for the national smart meter roll-out and continuing to invest in digital technology
A statement said: "Npower takes its responsibilities to its employees seriously and will consult fully with affected employees and with unions over its proposals for the future of the business."
Npower is to cut 2,400 jobs after reporting losses of over £100 million, the energy giant announced.
The cuts represent more than a fifth of the firm's 11,500-strong UK workforce.
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