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Big Six reviews


By Sarah Ingrams

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Npower is one of the UK's Big Six energy companies. But is Npower cheap and is its customer service any good? We reveal all.

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 more than 4.5 million domestic and business 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 joint 28th in our energy companies satisfaction survey this year. This is the first time that Npower hasn't finished in last position in the Which? energy companies survey. This year, it’s joint 28th with Scottish Power, and two firms rank lower.

We have scores for 30 energy companies, rated by 7,429 members of the general public.

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 why it wanted to merge with rival SSE.

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 first time, Npower is clear of the bottom of the table. Previously, it had always had the lowest customer score of all the energy companies included in our survey. But this year, small firm Solarplicity is the worst energy company, with Spark Energy also ranking lower than Npower.

Npower's other brand, Sainsbury's Energy, finished in 20th position, with higher star ratings on every aspect we asked about. However, British Gas was Sainsbury's Energy's supply partner when we ran the survey.

Npower scored a consistent two out of five stars on every measure we asked its customers about, from billing to customer service and value for money. So it still has some way to go to really impress customers.

Npower value for money

Customers also rate Npower as poor value for money overall; it was one of just two firms to score two stars for this in our survey. The other was British Gas.

People told us that the main reason they left Npower was because its prices were too high. Some 58% of ex-customers we spoke to said that this was among their top three reasons for switching.

Npower’s standard variable tariff was the priciest of the Big Six energy companies for part of 2018, and often £300 pricier per year on average than the cheapest deal on the market. But the energy price cap will limit some variable customers’ bills and it does sometimes offer cheap deals.

Npower customer service

Around two thirds of Npower’s customers said that its customer service was either good or excellent. That’s much better than the worst-scoring supplier (43%). However, more than 90% of customers of the top-scoring firms rate their customer service as good or excellent.

The foundation for improvement has been there for a while. Our evaluation of Npower’s procedures and practices*, including on product management and customer service, has found it to be well above average for three years running. This year it had the highest score, 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 that Npower took 7mins 21secs on average to put us through to a human when we phoned its customer services. 

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

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

Pros: Our analysis found its policies are better than those of many other suppliers

Cons: Pretty slow to answer the phone, customers don’t think it’s good value for money

*September 2018

Npower electricity sources

Npower energy prices

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

If you were an Npower customer and on its standard variable tariff, you could have saved a lot of money over the past year by switching to a cheaper energy deal – including Npower’s own cheapest fixed tariff. In summer 2018, Npower's standard deal was more than £100 pricier than its cheapest fixed deal, for the average user.

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 at the moment. 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.

February: Npower plans to increase prices by 10% from 1 April for around one million customers.

The announcement came just days after Ofgem announced that it would increase the level of the price cap for customers on standard or default tariffs from 1 April.

Affected Npower customers will pay £117 extra per year (based on a medium energy user).

Prepayment meter customers will see prices rise on the same day by £106 per 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. You could be affected if you have solar panels on your roof.

Quarterly statements showing the amount of money customers would receive as part of the feed-in tariff scheme also contained other customers’ names, addresses and payment amounts. No bank details were released, Npower said.

Find out your rights if your data has been lost.

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

Innogy, of which Npower is a subsidiary, said that preparations for the new merged energy company are ‘on track’ and it should be listed on the London Stock Exchange in late 2018 or early 2019.

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. It said that the firms hadn’t provided sufficient evidence to address its concerns that the merger would result in a ‘substantial lessening of competition’ which could see some customers’ bills increase.

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.

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%.

March: Npower raised electricity prices by 15% and gas prices by 4.8% for customers on its standard tariff, adding £109 per year to the average energy bill.

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