What do we mean by Big Six Energy Suppliers?

When looking to find a new UK energy supplier, you may have come across the term ‘Big Six Energy Suppliers’. The Big Six Energy Suppliers are the main energy suppliers within the UK and are known as the ‘Big Six’. They are:

They provide energy to more homes and properties than other smaller energy providers, who may be able to offer more flexible rates and greener fuels.  Although these companies don’t have a monopoly, they do dominate the market for the supply of gas and electricity.

The ‘Big Six’ was created when the 1989 Electricity Act led to the privatisation of our Central Electricity Generating Board (CEGB), which involved a series of mergers and acquisitions which, essentially, boiled down the industry to these top six companies.

Who are the Big Six Energy Suppliers?

British Gas

British Gas was formed after a number of gas companies and boards merged into one super-company in 1973, known as British Gas Corporation at the time. British gas is possibly the most famous energy company in the UK, serving approximately 70,000 households.

E.ON

E.ON was previously known as Powergen, which was formed following the 1989’s Electricity Act. The company was renamed to the current and better known E.ON, after a German energy franchise, E.ON AG, acquired Powergen in 2002.

EDF

EDF is owned by the French Électricité de France group, and is a gas and electricity provider who launched in 2002 after the merger of SEEBOARD, London Electricity, SWEB Energy, and British Energy.

SSE

Formerly known as Scottish and Southern Energy, SSE was formed following a merger of sections of the Southern Electricity Board and the North of Scottish Hydro-Electric Board. The company provides gas production, storage, exploration, and metering.

Scottish Power

A former section of the South of Scotland Electricity Board, Scottish Power is owned by the Spanish Iberdrola group of companies. Confusingly, Scottish power covers not just Scotland, but many other parts of England too.

Npower

Founded as Innogy in 2000, this German owned company provides gas and electricity. Npower, previously also known as National Power, also provide services where they specialise in boiler repairs and central heating systems.

What is the Big Six market share?

The Big Six energy companies hold between them around 75% of the UK’s energy supply. Outside of the Big Six, there are around 60-70 companies in the UK sharing only a quarter of the market share. The Big Six can be broken down as follows:

Supplier

British Gas
SSE
E.ON
EDF Energy
Npower
Scottish Power

Market Share

17 million customers
9 million customers
7 million customers
6 million customers
5 million customers
5 million customers