William Henry Porter (23 August 1862 – 27 June 1935), known as Sir William Porter, 2nd Baronet, of Frimley in the County of Surrey from 1895 was an Irish-born barrister and Conservative Party politician. The son of George Hornidge Porter, surgeon in ordinary to Queen Victoria in Ireland. His father was created a baronet in 1889, and William inherited the title on his death in 1895. At the 1895 General Election he unsuccessfully stood for election to the Commons at Tower Hamlets, Whitechapel. From 1899-1901 he was a Moderate Party alderman of the London County Council.