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24 January 2021


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?
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, and supplies around 3.6 million UK customers.

Npower is now majority owned by Eon, although the two remain separate companies for the moment. Npower's customers will gradually be moved over to Eon Next – a subsidiary of the company.

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 (CMA) gave it the provisional go-ahead.

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

Read on to find out what Npower’s customers think of it and 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 25th out of 25 firms in our energy companies satisfaction survey this year to occupy the very bottom spot below all its big rivals – British Gas, EDF Energy, Eon, SSE and Scottish Power.

We asked 7,460 members of the general public to rate their energy supplier to reveal the best and worst firms according to their customers.

The left hand doesn't know what the right hand is doing. Conflicting answers given.

Npower customer

I think it could lower the price it charges.

Npower customer

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 and where it gets its fuel from.

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 have returned. For several years in a row it had the lowest customer score of all the energy companies included in our survey. Two years ago it moved clear of the bottom by a couple of places and last year it was 30th out of 35 firms.

This year, it shares its woeful one-star rating for value for money with the other worst performers, Scottish Power and SSE. Five other companies were rated a poor two stars for this – Ecotricity , E and traditional big firms British Gas, EDF Energy and Eon. 

Customers were reasonably satisfied with Npower’s customer service this year, giving it a fair three-star rating overall. 

It also scored three stars for the accuracy of its bills, but just two for bill clarity and how it handles complaints. 

Official data on how many complaints it receives show that Npower received a fairly high number of complaints in the first half of 2020 compared with other suppliers. There were more than 17 complaints per 1,000 Npower customers, while several other firms received fewer than three.

Npower resolved just 57% of these within two days but the majority of them within eight weeks. 

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.  

I think I pay more than I should for the amount of electricity I use.

Npower customer

I always find the bills complicated. They are never put in easy-to-read terms.

Npower customer

When we investigated energy companies' customer service waiting times in September and October 2020, we found that Npower took 21 minutes 41 seconds on average to put us through to a human when we phoned its customer services. 

That’s significantly longer than average (5 minutes 57 seconds across the 31 firms we included). Only three other providers, including rival British Gas, were slower.

It was much faster to use Npower's live chat; we found we got a human response in 4 minutes 18 seconds on average in our investigation.

Pros: Fair customer service according to its customers 

Cons: Poor value for money; slow to answer the phone

Npower electricity sources

Npower in the news

Npower in 2020

September: Npower increased the cost of its off-peak night-time tariffs to bring it in line with the price cap set by energy regulator Ofgem, resulting in some customers' bills increasing by hundreds of pounds a year. 

Npower in 2019

November: Npower revealed that it lost 447,000 customers in the first nine months of 2019 as customers switched away from the traditional big firms.

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 has changed yet - you are still supplied and have customer service from Npower. Customers will gradually be moved over to Eon subsidiary Eon Next. 

April: Npower became the supply partner for Sainsbury's Energy. Through this brand it would sell 100% renewable electricity tariffs and 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.

Npower in 2018

December: Npower and SSE's proposed 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 would now be assessing different options for Npower's future.

Don’t pay too much for energy – use Which? Switch to find the cheapest gas and electricity deal.

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