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Big Six reviews


By Sarah Ingrams

Article 3 of 6

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Eon is one of the UK’s largest energy companies. Find out if Eon is the best gas and electricity supplier for you, as revealed by its customers.

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 is now the second-largest energy supplier in Great Britain, after it gained around 50,000 new customer accounts last year. It supplies 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 if Eon will save you money on energy – use Which? Switch to compare gas and electricity prices.

Eon customer score

Eon came joint 23rd out of the 30 energy companies, rated by 7,429 members of the public, in the annual Which? customer survey. It ranks jointly with EDF Energy again this year, but they’re not the highest-ranked of the Big Six firms.

Regardless, it still has room for improvement in comparison with the top-scoring smaller suppliers.

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, what its prices are like and the full Which? 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 consistent three stars in every category but one in our survey. That’s not bad, but customers were less impressed with the clarity of its bills, which were rated just two stars. Rival EDF scored three stars across the board. 

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

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

It has recently started offering customers on fixed tariffs the option to pay £2 extra per month for ‘clean’ energy. This means it’s backed by 100% renewable electricity. Eon’s other electricity tariffs are 10% coal-generated.

Eon's customer service

We found Eon was among the five slowest energy companies, on average, to answer the phone to its customers in our snapshot investigation into energy call waiting times

It took 17 minutes 29 seconds on average for us to get through to a human – the fastest company average, from small supplier Affect Energy, was just 10 seconds.

Eon offers live chat on its website and our investigation also found it was much faster to get a response from a human in this way, in 4 minutes 3 seconds on average. But other firms were far quicker; the fastest took just 10 seconds on average to respond on live chat.

Compared with other Big Six suppliers, it sources the greatest proportion of its electricity from coal (see its full fuel mix, below).

Pros: Offers some competitive fixed tariffs

Cons: Slow to answer the phone to its customers and live chat often wasn’t available in our investigation

Eon electricity sources

Eon energy prices

The graph above shows how Eon’s variable (also known as standard) tariff, its priciest tariff (where different to its standard tariff) and its cheapest tariff compared with the cheapest tariff on the market over the last two years.

As you can see, if you were an Eon customer you could have saved a lot of money if you’d switched to a cheaper energy deal with a different supplier, although it has offered many deals much cheaper than its standard tariff too.

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 3.3million 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 1.8m customers will be affected by the 10% price increase, adding £117 per year to the annual bills of customers who use a medium amount of gas and electricity.

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

June: Eon announced it will raise prices by 4.8% for gas and electricity customers on its standard variable tariff from 16 August.

For some customers, this will be the second time their bills have increased in 2018. The price rise means affected customers will pay £55 more per year on average. Eon said its price increase was due to ‘the significant rise in the cost of wholesale energy’.

April: Eon customers on its standard tariff saw their bills increase from 19 April 2018, after the energy firm scrapped dual-fuel and paperless billing discounts worth £30 per year.

Plus customers who pay by cash or cheque saw their standing charge rise by around £20 each year.

Although this isn’t a direct price increase, customers can see up to a 2.67% increase on their bills over the next year.

March: Two money-saving initiatives were scrapped, Eon announced on the coldest March day on record. From 19 April, Eon customers on its standard variable tariff stopped receiving dual-fuel and paperless billing discounts. Together these were worth £30 per year. 

Eon also increased the standing charge for customers paying by cash or cheque.

November: 200,000 customers switched away from Eon this year, the firm announced. 

October: Eon launched a tariff for owners of electric and hybrid vehicles, which is backed by 100% renewable electricity and green gas. 

September: Eon announced it will replace its standard variable tariff with a cheaper fixed-term tariff from early 2018, for customers who have a smart meter fitted. Customers with a smart meter will be put onto a one-year fixed tariff with no exit fee, which will ‘roll over’ onto the latest fixed deal when their tariff ends. Eon said it’s also ‘working on options for classic meter customers’.

April: Eon also increased its gas and electricity prices by 8.8% and 2.5 million customers saw bills increase by £97 over the following year.

February: Eon came joint 80th in a Which? survey of 100 of the biggest brands rated for customer service. Its customer service score was 72%.