The United Kingdom Central Electricity Board (CEB) was established by the Electricity (Supply) Act 1926. It had the duty to supply electricity to authorised electricity undertakers, to determine which power stations would be 'selected' stations to generate electricity for the board, to provide main transmission lines to interconnect selected stations and electricity undertakers, and to standardise generating frequency.

In 1925 Lord Weir chaired a committee that proposed the creation of the Central Electricity Board to link the UK’s most efficient power stations with consumers via a ‘national gridiron’. At that time, the industry consisted of more than 600 electricity supply companies and local authority undertakings, and different areas operated at different voltages and frequencies (including DC in some places). The board's first chairman was Andrew Duncan.

The CEB established the UK's first synchronised AC grid, running at 132 kilovolts and 50 Hertz, which by 1933 was a collection of local grids, with emergency interlinks, covering most of England. This started operating as a national system, the National Grid, in 1938.

After completion of the National Grid the role of the CEB changed from planning and construction to operating and managing the regional grid systems.

The CEB established laboratories at Croydon and Waddon to undertake research on high voltage transmission problems.

The CEB co-existed with the Electricity Commissioners, an industry regulator responsible to the Ministry of Transport.

The CEB ceased to exist when the electricity industry was nationalised by the Electricity Act 1947 and taken over by the British Electricity Authority.

There were four chairmen of the Central Electricity Board between 1927 and 1948: