South Ockendon is a town, former civil parish and Church of England parish within the Thurrock borough in Essex in the East of England, United Kingdom. It is located on the border with Greater London, just outside the M25 motorway. The area to the north is North Ockendon. In 2019 it had an estimated population of 22,303 and in the 2021 United Kingdom census it had a population of 22,442