Orsett Rural District was a local government district centred on Orsett in the south Essex part of the Thames Estuary in England. It was a rural district from 1894 to 1936, initially made up of seventeen civil parishes and the successor to the Orsett Rural Sanitary District. Parts of the district were split off to form Tilbury in 1912, Purfleet in 1929 and Billericay in 1934. Thurrock Urban District was the main successor district in 1936. Today it corresponds to the Thurrock unitary authority area with parts in Basildon, Essex and Havering, Greater London.