John Sydney Swan (12 January 1874 – 18 April 1936) (sometimes seen as Sidney) was a New Zealand architect, the designer of houses and churches in Wellington, New Zealand. He was articled to Frederick de Jersey Clere and was at one time a partner with Clere. Buildings he designed include Erskine College and the St Gerard's church section of the St Gerard's Church and Monastery, Our Lady of Compassion Convent, Island Bay (1908-1921) for Suzanne Aubert and various commercial buildings, houses and Wellington Harbour Board buildings.^[1][2]

He was born and died in Wellington. He married Gertrude Mary Holcroft in 1899, they had three sons and one daughter.^[3] He built his own home, The Moorings, in Glenbervie Terrace, Thorndon in 1905. The house has nautical themes running throughout, a reflection of his interest in sailing.^[4] His younger brother Francis Herbert Swan (1885–1956) also lived in Glenbervie Terrace, and in 1915 they formed an architectural partnership; Swan and Swan; later Swan, Lawrence and Swan with Charles Lawrence. Toward the end of his career Swan formed a partnership with Jim Lavelle as Swan and Lavelle.^[1]

He was a yachtsman, and Commodore of the Royal Port Nicholson Yacht Club. When he died in 1936 it was said he had one of the finest collections of ship photographs in the world.^[5]

• Fearnley, Charles (1977). Early Wellington Churches. Wellington: Millwood Press. p. 220.
• Obituary in Evening Post, Wellington of 20 April 1936
• Obituary in New Zealand Herald, Auckland of 21 April 1936
• Obituary in Auckland Star, Auckland of 22 April, 1936
• Erskine College Chapel, plan by John Swan