The electrical power industry in the United Kingdom was nationalised by the Electricity Act 1947, when over six hundred electric power companies were merged into twelve area boards.

List of companies

Companies merged into East Midlands Electricity Board (EMEB)

The board's area was defined as: Leicestershire, Northamptonshire, Rutland and parts of Bedfordshire, Buckinghamshire, Derbyshire, Lincolnshire, Nottinghamshire, Staffordshire and Warwickshire.

Local authority undertakings

Private companies

Companies merged into Eastern Electricity Board (EEB)

The board's area was defined as: Cambridgeshire, Hertfordshire, Huntingdonshire, the Isle of Ely, Norfolk, Suffolk and parts of Bedfordshire, Buckinghamshire, Essex, Middlesex, Oxfordshire and the Soke of Peterborough.

Local authority undertakings

Private companies

Companies merged into London Electricity Board (LEB)

The board's area was defined as: The administrative County of London and parts of Essex, Kent, Middlesex and Surrey.

Local authority undertakings

Joint electricity authority

Created under the provisions of the Electricity (Supply) Act 1919

Private companies

Companies merged into Merseyside & North Wales Electricity Board (MANWEB)

The board's area was defined as: Anglesey, Caernarvonshire, Denbighshire, Flintshire, Merionethshire, Montgomeryshire and parts of Cardiganshire, Cheshire, Lancashire (including Liverpool) and Shropshire.

Local authority undertakings

Joint electricity authority

Created under the provisions of the Electricity (Supply) Act 1919

Private companies

Companies merged into Midlands Electricity Board (MEB)

The board's area was defined as: Herefordshire, Worcestershire and parts of Gloucestershire, Oxfordshire, Shropshire, Staffordshire and Warwickshire (including Birmingham).

Local authority undertakings

Joint electricity authorities

Created under the provisions of the Electricity (Supply) Act 1919

Private companies

Companies merged into North Eastern Electricity Board (NEEB)

The board's area was defined as: Durham, Northumberland, the North Riding of Yorkshire and parts of the East and West Ridings of Yorkshire (including York).

Local authority undertakings

Private companies

Companies merged into North Western Electricity Board (NORWEB)

The board's area was defined as: Cumberland, Westmorland and parts of Cheshire, Derbyshire, Lancashire (including Manchester) and of the West Riding of Yorkshire.

Local authority undertakings

Private companies

Companies merged into South East Scotland Electricity Board

The board's area was defined as: Berwickshire, Clackmannanshire, Fife, Lothians (East Lothian, Midlothian, West Lothian), Peebles, Selkirkshire, and parts of Dunbartonshire, Roxburghshire and Stirlingshire.

Local authority undertakings

Private companies

Companies merged into South Eastern Electricity Board (SEEBOARD)

The board's area was defined as: Parts of Kent, Middlesex, Surrey and Sussex.

Local authority undertakings

Joint electricity authority

Created under the provisions of the Electricity (Supply) Act 1919

Private companies

Companies merged into South Wales Electricity Board (SWALEB)

The board's area was defined as: Brecknockshire, Carmarthenshire, Glamorganshire, Monmouthshire, Pembrokeshire, Radnorshire and part of Cardiganshire.

Local authority undertakings

Private companies

Companies merged into South West Scotland Electricity Board

The board's area was defined as: Ayrshire, Dumfries-shire, Glasgow, Kirkcudbrightshire, Lanarkshire, Renfrewshire, Wigtownshire and parts of Dunbartonshire, Roxburghshire and Stirlingshire.

Local authority undertakings

Private companies

Companies merged into South Western Electricity Board (SWEB)

The board's area was defined as: Cornwall (including the Isles of Scilly), Devonshire and parts of Dorsetshire, Gloucestershire (including Bristol) and Somersetshire.

Local authority undertakings

Private companies

Companies merged into Southern Electricity Board (SEB)

The board's area was defined as: Berkshire, Hampshire, the Isle of Wight, Wiltshire and parts of Buckinghamshire, Dorsetshire, Gloucestershire, Middlesex, Oxfordshire, Somersetshire, Surrey and Sussex.

Local authority undertakings

Private companies

Companies merged into Yorkshire Electricity Board (YEB)

The board's area was defined as: Parts of Derbyshire, Lincolnshire, Nottinghamshire and of the East and West Ridings of Yorkshire.

Local authority undertakings

Private companies

Other companies

The following companies had interests in multiple and non-contiguous locations.

Footnotes