The Municipal Borough of Farnworth was a local government district centred on the town of Farnworth in the administrative county of Lancashire, England. A local board of health had been established for Farnworth in 1863, which was reconstituted as an urban district in 1899, before being granted a charter of incorporation to become a municipal borough in 1939. Following abolition of the local authority in 1974, Farnworth became an unparished area of the Metropolitan Borough of Bolton in Greater Manchester.

Lying within the boundaries of the historic county of Lancashire since the early 12th century, Farnworth constituted a township in the civil and ecclesiastical parish of Deane. In 1837, Farnworth became part of the Bolton Poor Law Union which took responsibility for funding the Poor Law in that Union area.

Under the Local Government Act 1858, a local board of health was adopted for the township of Farnworth in 1863. In 1866, Farnworth was also given the status of a civil parish. After the Public Health Act 1875 was passed by Parliament in that year, Farnworth Local Board of Health assumed extra duties as an urban sanitary district, although the Local Board's title did not change.

In 1899, following the implementation of the Local Government Act 1894, Farnworth Local Board was reconstituted as an elected urban district council of eighteen members. Farnworth Urban District Council had six electoral wards, each denoted by points of the compass (North, North-East, North-West, South, South-East, and South-West wards), and each represented by three councillors. In 1939, Farnworth was granted a charter of incorporation to become a municipal borough.

Under the Local Government Act 1972, the Municipal Borough of Farnworth was abolished on 1 April 1974 and its former area was transferred to Greater Manchester to become an unparished area of the Metropolitan Borough of Bolton.

Population changes of Farnworth, 1891–1971

Year Population ±% 1891 23,758 —     1901 25,925 +9.1% 1911 28,131 +8.5%	Year Population ±% 1921 27,894 −0.8% 1931 28,717 +3.0% 1939 27,376 −4.7%	Year Population ±% 1951 28,616 +4.5% 1961 27,502 −3.9% 1971 28,855 +4.9%
Sources: Urban Sanitary District (USD) 1891. Urban District (UD) and Municipal Borough (MB) 1901–1971.

Chairmen of Farnworth Local Board, 1863–1899
Name		Party	Tenure	Notes
	Alfred Barnes	Liberal	1863–1867	1st term
	David Crossley	Liberal	1867–1868
	John Hindley	Conservative	1868–1869
	Alfred Topp	Liberal	1869–1870	1st term
	William Barton Whittam	—	1870–1872	1st term
	John Greenhalgh	—	1872–1875
	Alfred Topp	Liberal	1875–1878	2nd term. Afterwards was Chairman of Farnworth Urban District Council (1901–1904)
	Alfred Barnes	Liberal	1878–1880	2nd term
	William Barton Whittam	—	1880–1881	2nd term
	James Nuttall	Liberal	1881–1885
	Joseph Winter	Liberal	1885–1886
	George Foster	Liberal	1886–1887
	John Clelland Clarke	Liberal	1888–1894
	Nathaniel Nicholson	Conservative	1895–1897
	Thomas Ivers	Liberal	1897–1899
Source(s):

Chairmen of Farnworth Urban District Council, 1899–1939
Name		Party	Tenure	Notes
	William Sumner	—	1899–1901
	Alfred Topp	Liberal	1901–1904	Previously Chairman of Farnworth Local Board (1869–1870, and 1875–1878)
	Thomas Ivers	Liberal	1904–1906
	Thomas Stanley	Conservative	1906–1909
	Frederick Whittaker	Conservative	1909–1912
	Charles Young	Conservative	1912–1914
	William Boyes Richardson	Liberal	1914–1915
	James Stones	Conservative	1915–1919
	John Chadwick	Conservative	1919–1921
	Charles Strathnairn Jackson	Labour	1921–1923
	Richard Henry Cunliffe	Liberal	1923–1925
	Thomas White	Conservative	1925–1926
	Walter Robert Winter	Labour	1926–1928
	Harry Barnes	Labour	1928–1930
	The Rev. John Wilcockson	Labour	1930–1932	Afterwards was Mayor of Farnworth (1939–1940)
	George Tomlinson	Labour	1932–1933	Afterwards was Member of Parliament for Farnworth (1938–1952)
	James Stevenson	Labour	1934–1936	Afterwards was Mayor of Farnworth (1940–1941)
	Samuel Taylor	Liberal	1936–1937
	Alfred Jones	Labour	1938–1939	Afterwards was Mayor of Farnworth (1941–1942)
Source(s):

Mayors of the Municipal Borough of Farnworth, 1939–1974
Name		Party	Tenure	Notes
	The Rev. John Wilcockson	Labour	1939–1940	Previously Chairman of Farnworth Urban District (1930–1932)
	James Stevenson, JP	Labour	1940–1941
	Alfred Jones, JP, OBE	Labour	1941–1942	Previously Chairman of Farnworth Urban District (1938–1939)
	William McManus	Labour	1942–1943
	John Heathcoate	Labour	1943–1944
	Jesse Seddon, JP, MC	Conservative	1944–1945
	Richard Ralphson	Labour	1945–1946
	Harold Greenwood Holland	Labour	1946–1947
	James Alfred Dean	Labour	1947–1949
	William Welsby	Labour	1949–1950
	John Brooks	Labour	1950–1951
	George Henry Wilson	Liberal	1951–1952
	Richard Matthews	Labour	1952–1953
	Harold Armitage	Labour	1953–1954
	Robert Neary, JP	Labour	1954–1955
	James Melville White	Labour	1955–1956
	James Wilfred Geere	Labour	1956–1957
	John Glanville Seddon	Labour	1957–1958
	George Benyon	Labour	1958–1959
	John Higgins	Labour	1959–1960
	Albert Samuel Royse, JP, MBE	Conservative	1960–1961
	Herbert Brindle	Labour	1961–1962
	Philip Smith	Labour	1962–1963
	Phillip Norfield	Labour	1963–1964
	Sydney Stout	Labour	1964–1965
	George Kenyon Brown	Labour	1965–1966
	Norman Topping	Labour	1966–1967
	Charles Brendan Callaghan	Labour	1967–1968
	Lawrence Francis Cunliffe	Labour	1968–1969
	Joseph Wild	Labour	1969–1970
	Leonard Haslam	Labour	1970–1971
	William Hardman	Labour	1971–1972
	Elizabeth Brown	Labour	1972–1973
	Joseph Kenneth Flanagan	Labour	1973–1974
Source(s):

The Municipal Borough of Farnworth was surrounded to the north and west by the County Borough of Bolton, to the northeast by Little Lever Urban District, to the southeast by Kearsley Urban District, and to the south by Little Hulton Urban District until 1933, then by Worsley Urban District.

• Boundary Map of Farnworth UD/MB

53°32′43″N 2°24′00″W / 53.5452°N 2.3999°W / 53.5452; -2.3999