Augustus Alwin Farnham (20 May 1805 – 2 May 1865^[1]) was an architect in Utah and a Mormon missionary.^[2]

Farnham was born May 20, 1805, in Andover, Massachusetts.^[2] In 1843, Farnham converted to Mormonism. In 1845, he was ordained a Seventy and was called to a mission in Australia, arriving in Sydney in 1851. From 1853 to May 1856, he was the president of the mission^[2] In October 1854, Farnham, William Cooke, and Thomas Holder traveled to Auckland and became the first missionaries of the Church of Jesus Christ of Latter-day Saints in New Zealand.^[3] The three preached in Auckland, Wellington, and Nelson, after which Farnham returned to Australia, leaving Cooke and Holder to continue preaching.^[3]

Farnham's most important architectural work was the Bountiful Tabernacle, a Greek Revival monument, which was known worldwide.^[2] This building, located at Main and Center Streets in Bountiful, Utah, is listed on the U.S. National Register of Historic Places.