An 1888 Act of Parliament created County, District and Civil Parish Councils.
Prior to this local administration was by the Parish Vestry , a committee of local people under the chairmanship of the vicar. This combined the roles of the present day parish council and the parochial church council.
In the early 1830s Gwennap Ecclesiastical parish, which then included St.Day, Carharrack, Lanner, Scorrier, Crofthandy, Cusgarne and Frogpool, was the most highly populated in the county due to the prosperity of the local mines.
St. Day became a separate ecclesiastical parish in 1835, with its own vicar, following the building of a new church (now the Old Church) .
As a result of a meeting held in St. Day in 1894 the civil parish of Gwennap was formed which included St. Day and the other villages. Gwennap was then part of Redruth Rural District Council until 1934.
Further legislation led to the creation of the Camborne Redruth Urban District Council in 1934 which included St. Day along with Carharrack, Lanner and other villages. Urban Districts did not have parish councils.
The remaining parts of Gwennap Parish became part of Truro Rural District Council and, being a rural district, retained parish councils and later in 1974 became part of Carrick District.
1974 saw the merger of Camborne- Redruth with Helston and the surrounding areas to become Kerrier District Council. A later act allowed the formation of parish councils in the new districts, so St. Day was permitted to form its parish council in 1985. The parish covers the settlements of Busveal and (most of) Scorrier as well as the township of St. Day.
In 2009 Cornwall County Council and the 6 District Councils were merged to form Cornwall Council as a unitary authority.
The parishes of Carharrack, Gwennap and St. Day now form a ward of Cornwall Council, retaining their respective parish councils.