Alexander Charles Garrett (November 4, 1832 — February 18, 1924) was a bishop of The Episcopal Church in the United States.

Born in Ballymote, County Sligo, Ireland, he graduated from Trinity College, Dublin with a Bachelor of Arts in 1855.

In 1859 he left for British Columbia in Canada to serve as missionary, chaplain at the naval station at Esquimalt, rector of St Paul's Church in Nanaimo, and minister to the gold miners at Cariboo.

In 1870 he moved to the United States and became rector of St James's Church in San Francisco, and in 1872 Dean of Trinity Cathedral in Omaha.

In 1874 he was appointed Missionary Bishop of Northern Texas and retained the seat after the formation of the Episcopal Diocese of Dallas on December 20, 1895.