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1 October 2020


Npower was one of the original energy companies in Great Britain. Now that it's owned by rival Eon, how will it change? And does it offer good customer service and low prices in the meantime?
Npower big six 480405
Sarah Ingrams

Npower is part of the Innogy group, a Europe-wide energy company based in Germany. It operates coal, oil, biomass and gas-fired power stations.

Npower is now majority owned by Eon, although the two remain separate companies for the moment. Previously, Npower planned to merge with SSE, but the deal was called off in December 2018, just a few months after the Competition and Markets Authority gave it the provisional go-ahead.

Then in April 2019 it became the supply partner of Sainsbury's Energy.

Npower supplies around 2.3 million customers.

Read on to find out what Npower’s customers think of it, and to see whether 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 30th out of 35 firms in our energy companies satisfaction survey this year, a few points below most of its big rivals – British Gas, EDF Energy, Eon and SSE. Its other big competitor, Scottish Power, is ranked lower.

We asked 7,355 members of the general public to rate their energy supplier to reveal the best and worst firms, according to their customers.

Npower score breakdown

See below for the breakdown of Npower’s score from our latest survey.

Then scroll down to find out more about Npower’s prices, where it gets its fuel from, and the latest on what Eon’s acquisition means for 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

Npower’s days at the very bottom of the table seem to be over. For several years in a row, it had the lowest customer score of all the energy companies included in our survey. But last year it moved clear of the bottom by a couple of places, and this year it’s well clear.

Instead, small firm Together Energy takes the bottom spot.

Npower's other brand, Powershop, finished in joint-fifth position, with higher star ratings on every aspect we asked about. 

Its two-star rating for value for money equals that of the lowest-ranked suppliers. However, seven companies overall were rated poor for value for money by customers in our survey. These included British Gas, EDF Energy and Scottish Power.

Customers weren’t complimentary about Npower’s customer service, giving it a poor two-star rating overall. When we investigated energy companies’ customer service waiting times, we found that Npower took 7mins 21secs on average to put us through to a human when we phoned its customer services. 

While that’s significantly longer than average (4mins 24secs across firms we included), Npower was faster than rival Scottish Power, which took more than 21 minutes to answer our calls on average.

It was much faster to use Npower's live chat; we found we got a human response in 2mins 29secs on average in our September 2019 investigation.

It scored slightly better on other aspects of service, including how it handles complaints. Npower still has a long way to go to rival the best firms, however.

Official data on how many complaints it receives show that Npower received a fairly high number of complaints in the first half of 2019 compared with other suppliers. There were more than 20 complaints per 1,000 Npower customers, while several firms received two or fewer.

Npower resolved just over half of these within two months. The best firms manage nearly 100% in this time.

Npower’s digital tools were considered average by customers, although just six firms in our survey achieved a higher score.

In recent years, our evaluation of Npower’s procedures and practices*, including for its product management and customer service, has found that Npower has a strong foundation for improvement. This year it had the third-highest score of the firms included, although it still has a lot of work to do to keep its customers satisfied.

Since Npower is now majority owned by Eon, customers may see changes over the next year. However, it’s business as usual for the moment.  

Pros: Our analysis found its procedures and practices are better than those of many other suppliers

Cons: Poor value for money with poor customer service, according to customers

*Latest evaluation in September 2019

Npower electricity sources

Npower in the news

September: Npower announced that it is now majority owned by Eon. The EU Commission approved the takeover of Npower’s parent company, Innogy, by Eon.

If you’re an Npower customer, nothing is changing yet. You will still be supplied and have customer service from Npower. It will contact customers if things change in future.

April: Npower became the supply partner for Sainsbury's Energy. Through this brand it will sell 100% renewable electricity tariffs, and will reward customers with Nectar points.

It increased prices by 10% at the start of the month, adding £117 to the annual bills of around one million customers (based on a medium energy user).

Prepayment meter customers saw prices rise by £106 a year.

December: Npower and SSE's merger plan was scrapped. Innogy SE, Npower's parent company, said the two firms 'could not agree on a joint solution for the necessary direct and indirect financial contributions'.

It said 'adverse developments in the UK retail market', and the default energy tariff price cap were both partly to blame. It's now assessing different options for Npower's future. 

September: Npower shared personal details of 5,000 of its customers in letters posted to other customers. This affected solar panel customers. Data included names, addresses and payment amounts. No bank details were released, Npower said.

August: Npower and SSE’s merger was provisionally cleared by the CMA which said it ‘does not raise competition concerns’.

Earlier in the month, Npower was fined £2.4m by Ofgem for failing to install advanced meters for some of its electricity business customers by the 2014 deadline.

June: Npower increased prices by 5.3% for the one million customers on its standard variable tariff. This adds £64 to dual-fuel customers’ bills, on average, over the next year.

The increase made its standard tariff the most expensive of the Big Six energy suppliers, costing £1,230 per year for the average energy user.

May: The proposed merger with SSE was referred for further investigation by the CMA to determine whether to give it the go-ahead.

March: 155,000 customers left Npower over the past year. Npower Boss Paul Coffey said the losses ‘can largely be attributed to the first quarter’ of the year. This was after Npower increased its prices.

Npower reported a £56m loss last year and now has around 4.56 million customers.

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