Octopus has taken 24 per cent market share and serves 7.3 million customers in the UK, only nine years after launching to the market.

The ascension to the leadership position is the first time the top place has changed since the energy retail market opened for competition in the ‘90s.

Octopus Energy Group, which is valued at $9bn, is continuing to grow , both domestically and internationally, and is now active in 26 countries, serving nine million customers globally. It is also one of the largest specialist investors in renewables in Europe, managing a portfolio worth £7bn.

Octopus has also licensed its data and machine learning platform, Kraken, to over 60 million customer accounts worldwide through licensing deals with companies such as EDF, E.ON and Origin Energy.

Dan Morris, CEO at Cornwall Insight, says: "This is quite honestly the biggest development in the domestic retail energy market since it opened. Octopus Energy started from zero market share in 2015 and has worked its way up to the top spot on this measure in less than a decade. This is a notable achievement in the highly competitive and tightly regulated UK supplier market.”

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