The Big Six Are Now the Big Three After E.ON Takes Ovo
E.ON Next has completed its takeover of Ovo Energy with competition clearance, combining 5.6 million households with Ovo’s 4 million. The merged supplier holds about 25% of the market and 13.45 million accounts, second to Octopus. Almost three-quarters of British households are now served by three companies.
Octopus has about 26% and 14.3 million accounts; British Gas about 23% and 12.5 million. Add EDF and Scottish Power and five firms serve roughly 90% of the country. The number worth setting against that is historical: the old Big Six held about 85% in 2016, when a landmark competition inquiry concluded that customers were overpaying by something between £1.4bn and £1.7bn a year because competition was too weak. A decade of policy aimed at breaking that grip, a crisis that removed about thirty suppliers in 2021 and 2022, and the market has ended up more concentrated than when the inquiry reported. Tom Goswell of Cornwall Insight states the worry directly: “The big six have become the big three”, and “the concern with fewer suppliers is that the pressure to compete eases off, taking with it some of the incentive to keep prices low”. Chris Norbury, chief executive of E.ON UK, rejects that reading, calling the market “fiercely competitive” and arguing that scale lets the company “deliver for customers now and to transform for the energy system to come”. Nothing changes for Ovo’s four million customers today. What changes is how many places they can go if it does.