Cotton, William Francis (1841?–1917), businessman and politician, was born in Dublin, probably in 1841 (though WWW gives the date as 1847), the eldest son of Joseph W. Cotton, an iron founder specialising in the manufacture of gas lamps, meters, and burners at Clarendon Street, Dublin.
William Cotton studied chemistry and gas manufacture at the Polytechnic Institute of Dublin (later the Royal College of Science) before entering the employment of one of the Dublin gas companies. On 11 May 1861 he was appointed superintendent of lighting and gas examiner for Dublin corporation. When the Dublin gas companies were amalgamated in 1866 he encouraged the municipality to purchase the new company, the Alliance and Dublin Gas Consumers Co. but, although a deal was agreed in 1871, it was blocked by a parliamentary committee at Westminster. Cotton resigned from Dublin corporation in December 1873 (he was succeeded by his brother T. J. Cotton) to become secretary of the Alliance and Dublin Gas Consumers Co. He subsequently added the role of manager to that of secretary, and then served in succession as director, managing director (1898–1903), and chairman (1903–15); he was largely responsible for the success of the venture, and three of his sons also worked in senior positions in the company. His other directorships included the Dublin United Tramway Co., the Gas Meter Co. of London, and the Hibernian Bank. He was chairman of Alex Findlater & Co. and co-founder and chairman of the Hibernian Insurance Co.
An active member of the Irish parliamentary party, Cotton was an alderman (1899–1917) of Dublin corporation, and chairman of many corporation committees, most notably the Parnell monument committee. He was a magistrate, high sheriff (1901), and deputy lieutenant for Co. Dublin. He failed to become lord mayor in 1903 but succeeded to the office in 1911. In January 1910 he was a candidate at the general election for the seat of South County Dublin, but was narrowly defeated; he contended for it again the following December and won by a small margin. Despite retaining his seat until his death he never made his maiden speech.
Married twice, Cotton had four sons and a daughter. He lived at Hollywood, Roebuck, Dundrum, Co. Dublin. He died 8 June 1917 after a long illness leaving an estate valued at £29,685.