William Turnbull (1868 – 22 June 1941) was an architect based in Wellington, New Zealand.

He was the fourth and youngest son of architect Thomas Turnbull.

[3] In his younger years, he played rugby union at Poneke Football Club in Kilbirnie.

The outbreak of World War I caused the construction to be delayed until late 1915, with Alexander Turnbull moving in the following year.

[6] Turnbull moved to his son's house in Willis Street when he was old, and he died there on 22 June 1941,[7] aged 73.