Boyd Morehead was born in Sydney, New South Wales, the second son and child of two sons and two daughters (and the only son to reach full adulthood) of businessman Robert Archibald Alison Morehead and his wife Helen Buchanan, née Dunlop.
In 1873 he founded the well-known firm of B. D. Morehead and Company, general merchants, and stock and station agents, which afterwards became Moreheads Limited.