Big Six Energy Suppliers (UK)

The Big Six Energy Suppliers in Britain are generally taken to be Britain's largest energy suppliers, supplying gas and electricity to over 50 million homes and businesses in Britain, with over 90% share of domestic customers. "Supplier" is meant by the business of buying wholesale power (or gas), paying network and government policy costs and charges, and charging the customers of that supplier, for their electricity (or gas). The assets of a supplier, which is a separate licensed business, are its people, and its offices. The business of four of the big energy Suppliers, including of their wider company groups, does not entail owning, or running, any actual network assets - underground cables, overhead lines, or pipes - to physically deliver electricity or gas. The two exceptions to this, are the two big Scottish Supplier firms, whose wider company groups do own some network assets.

Confusingly, the term "Big Six" has recently been used prominently in the British media to refer, instead, to Britain's energy network firms such as UK Power Networks (which are generally independent of the biggest six British energy suppliers). There has also been a tendency in the media to wrongly refer to electricity network firms as "electricity suppliers", thus sowing further confusion and misunderstanding,

The "Big Six" as the term has most often been used, tends to be a reference to the oldest British electricity companies (which are all also involved in the retail Supply of gas) plus British Gas. This comprises (1) British Gas (owned by UK firm Centrica which is listed on the ), (2) EDF Energy (owned by French firm Électricité de France which is listed on the Paris Stock Exchange, (3) npower, (4) E.ON UK (each German-owned), (5) Scottish Power (Spanish-owned), and (6) SSE (listed on the ).

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