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1 October 2020


Eon is one of the UK’s largest energy companies. Find out whether Eon is the best gas and electricity supplier for you, as revealed by its customers.
Eon big six 480404
Sarah Ingrams

Eon is owned by German company Eon SE. It's one of the UK’s largest electricity generators and owns power stations, wind farms and biomass plants.

It's also one of the largest energy suppliers in Great Britain, after it gained around 50,000 new customer accounts last year. It provides energy to around 4.3 million homes and businesses. And this may be set to grow as Eon now owns the majority of Innogy, Npower's parent company.

Eon says it aims to lead the global shift towards new technology and be more sustainable. It sells solar panels and home batteries, and is installing electric vehicle charging points across the country.

See whether Eon will save you money on energy – use Which? Switch to compare gas and electricity prices.

Eon customer score

Eon came joint-24th out of the 35 energy companies, rated by 7,355 members of the public in the annual Which? customer survey. It ranks jointly with E and SSE this year, ahead of British Gas and Scottish Power.

It’s still far behind fast-growing rival Ovo Energy, showing there’s plenty of room for improvement.

Eon score breakdown

The graphic below shows the breakdown of its score from our latest survey.

Scroll down to find out how long it took to answer the phone to its customers in our snapshot investigation, if live chat is faster and our full verdict on Eon.

Find out how Eon compares with other energy companies – click to reveal the full results of the best and worst energy companies.

Which? verdict on Eon

Eon scores a respectable three stars out of five in four categories of six in our survey. That’s not bad, but customers of the highest-scoring brands achieved four stars or more. Jointly ranked SSE scored better (four stars) for customer service, but Eon’s rating for bill accuracy was higher.

Eon customers’ responses gave it a four-star rating for how it handles complaints too. Data from energy regulator Ofgem reveals that while Eon gets a high number of complaints per 1,000 customers compared with other firms, it solves the majority within eight weeks.

Eon’s customer service doesn’t stand out from the crowd, according to our survey.

We found that Eon took 9mins 8secs, on average, to answer the phone to its customers in our snapshot investigation into energy call-waiting times

That’s far from the fastest pick-up time (So Energy took an average of just 38 seconds), but far quicker than rival Scottish Power, which took more than 21 minutes to pick up the phone, on average.

Eon offers live chat on its website, and our investigation found it was faster to get a response from a human in this way – 4mins 36secs, on average. But live chat wasn't available a few of the times we tried, and other firms were far quicker – the fastest took less than a minute, on average, to respond.

Its tariff range includes an online-only tariff, a deal including boiler cover, and a tariff exclusively for electric and hybrid vehicle owners that gives customers a £30 reward for the equivalent of 850 miles of electricity.

Eon sometimes offers competitive dual-fuel tariffs, although customer opinions are mixed about its value for money.

All of its household customers get tariffs backed by 100% renewable electricity. However, the average for Eon’s domestic and small business customers overall is 27% renewable.

Pros: Offers competitive fixed tariffs sometimes, rewards electric vehicle drivers

Cons: Fairly slow to answer the phone to its customers, live chat sometimes wasn’t available in our investigation

Eon electricity sources

See how much money you can save on your energy bill. Use Which? Switch to find the cheapest gas and electricity.

Eon in the news

September: Eon got the go-ahead from the European Commission to take over Innogy, Npower’s parent company. Eon said it plans to integrate the two ‘swiftly’ and ‘create a company fully dedicated to putting customers at the centre’. But the two remain separate companies for the moment.

July: Eon announced that all of its 3.3 million domestic customers are provided with 100% renewable electricity at no extra cost.

It owns onshore and offshore wind farms, and biomass plants which will supply some of the renewable electricity. The rest will come from contracts with independent generators or be certified by renewable electricity guarantee certificates. These show that an equivalent amount of renewable electricity was generated to the amount supplied.

February: Eon was the first energy firm to announce that it would raise prices when the level of the price cap on standard and default tariffs is increased on 1 April.

Around 1.8 million customers were affected by the 10% price increase, adding £117 per year to the bills of customers who use a medium amount of gas and electricity.

Customers with prepayment meters saw £106 (9%) added to their bills per year.

June: Eon announced a 4.8% price rise for gas and electricity customers on its standard variable tariff from August.

This was the second time bills increased for some customers in 2018, adding £55 more per year, on average, to their bills.

April: Eon customers on its standard tariff saw their bills increase from April 2018, after the energy firm scrapped dual-fuel and paperless billing discounts worth £30 per year.

Customers who paid by cash or cheque saw their standing charge rise by around £20 each year.