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Energy company reviews


By Sarah Ingrams

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Npower has more than five million customers, making it one of the UK's Big Six energy companies. But is Npower cheap and is its customer service any good?

Npower is part of the Innogy group, a European-wide energy company based in Germany. Previously a subsidiary of RWE Group, its renewable energy, network and retail divisions, including Npower, were spun off into a separate business called Innogy SE in 2016.

Npower operates coal, oil, biomass and gas-fired power stations.

Keep reading to find out what Npower’s customers think of it and to see if Npower offers value for money.

See how Npower compares on price with your current deal – compare energy prices with Which? Switch.

Npower customer score

Npower came bottom in our energy companies satisfaction survey again, the seventh year in a row. It came last when compared with the 23 energy companies rated by 8,917 members of the public in the annual Which? customer survey – the biggest of its kind.

‘They seem to have reasonable tariffs when I have compared them but they are slow to pass on reductions’

Npower customer

The table below shows the breakdown of its score from our latest survey. Scroll down to find out more about Npower’s prices and where it gets its fuel from.

Npower survey results
Area of performance Star rating
Customer service and complaints handling
Value for money
Bills (accuracy and clarity)
Helping you to save energy
Customer score 44%

(Survey: October 2016, responses of 785 Npower customers.) 

Find out how Npower compares with other energy companies – we reveal the full results of the best and worst energy companies.

Which? verdict on Npower

For the seventh year running, Npower has the lowest customer satisfaction score of all the energy companies. 

Only a fifth of its customers told us they’re very satisfied, compared with more than a third of whom are very satisfied on average with other firms.

Customers also rate Npower as terrible value for money overall; it was the only firm to score one star for this in our survey. This is despite it sometimes offering cheap deals. Npower customers’ comments on value for money were mixed. One said: ‘It seems good value compared with my previous supplier.’ But another told us: ‘The bills are too high and there are no value-added services to compensate for this.’

Npower customer service

Analysis of our customer survey results revealed that, of the Big Six suppliers, Npower has the highest percentage of its customers joining because it offered a lower price than their previous supplier. But it’s the only Big Six supplier whose customers cite poor customer service as the second-biggest reason for leaving. This suggests customers are attracted by good prices but driven away in frustration at its service.

Customers are attracted by Npower’s good prices but driven away in frustration at its service

While some customers have found Npower’s customer services staff ‘very pleasant, polite, patient and helpful’, others have had a poor experience. This includes a customer who told us: ‘It takes ages to get through, then ages sorting out your query.’ Another customer said: ‘Npower appears to keep no record of current or previous complaints, so you have to keep repeating yourself; it takes far too long to respond.’

But the foundation is there for improvement. Our evaluation of Npower’s policies* including on product management and customer service,  found it to be above average, although it still has a lot of work to do to keep its customers satisfied.

Our investigation into energy companies’ customer service waiting times found Npower took over seven and a half minutes on average to put us through to a human when we phoned its customer services. It’s much faster to use live chat; we found we got a human response there in just 14 seconds on average.

Pros: Offers cheap deals and our analysis found its policies are better than those of many other suppliers

Cons: Customers don’t think it gives good value for money and it’s the lowest-scoring supplier again this year

*(September 2016)

Npower fuel mix

Where Npower gets its fuel from:

  • 66% natural gas
  • 16% coal  
  • 16% renewable
  • 1% nuclear
  • 1% other.

(Note: This information was correct as of January 2017.)

Npower energy prices

The graph below shows how Npower’s variable (also known as standard) tariff and its cheapest fixed tariff compared with the cheapest fixed tariff on the market over a two-year period. 

If you were an Npower customer and on its variable tariff, you could have saved a lot of money if you’d switched to a cheaper energy deal - including Npower’s own cheapest fixed tariff. In our latest figures, Npower's standard deal is £190 pricer than its cheapest fixed deal, for the average user.


November: Npower and SSE announced plans to merge into a new energy supplier.

Npower’s parent firm, the German company Innogy, would join its business supplying households in the UK with SSE’s, to form an energy company of a similar size to British Gas (the biggest of the Big Six firms).

September: Npower came joint-94th in a survey of 100 of the best and worst big brands for customer service, with a customer service score of 67%.

February: Npower announced that it was putting up electricity prices by 15% and gas prices by 4.8% for customers on its standard tariff. The rise will take effect from 16 March and increase the cost of a typical dual fuel energy bill by £109 on average over a year. 

Energy regulator Ofgem said: 'We don't see any case of significant price increases where suppliers have bought energy well in advance. Npower must therefore justify the decision to its customers.'


In March, Npower reported an annual loss of £99m for 2015. This came after a series of customer service failings and a £26m fine from the regulator Ofgem, announced at the end of 2015 (see below). 


Regulator Ofgem announced that Npower was being fined £25m in December. The fine came after Ofgem found that Npower’s billing issues affected more than 500,000 customers between September 2013 and December 2014, and that Npower failed to handle complaints effectively within a reasonable time frame. 

Ofgem announced in July that its investigation found that some Npower customers’ ombudsman rulings have been left outstanding for more than 28 days. Ofgem has ensured that the 1,000 customers affected will receive free energy until Npower has fully implemented the rulings and will have any debt on their account written off.

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