Essex (/ˈɛsɪks/ ESS-iks) is a ceremonial county in the East of England. It is bordered by Cambridgeshire and Suffolk to the north, the North Sea to the east, Kent across the Thames Estuary to the south, Greater London to the south-west, and Hertfordshire to the west. The largest settlement is Southend-on-Sea.
The county has an area of 3,670 km (1,420 sq mi) and had an estimated population of 1,929,610 in 2024. The south of the county is densely populated, and includes Southend-on-Sea in the south-east and Basildon in the south-centre. The centre and north of the county is more rural, and its principal settlements include Chelmsford in the centre and Colchester in the north-east. The districts of Chelmsford, Colchester and Southend hold city status. For local government purposes Essex comprises a non-metropolitan county, with twelve districts, and two unitary authority areas: Thurrock and Southend-on-Sea. The county historically included north-east Greater London, the River Lea forming its western border.