Heriot was the court goldsmith to Anne of Denmark, the wife of King James VI of Scotland, as well as to the king himself; he became very wealthy from this position, and wealthier still as a result of lending this money back to the king and the rest of his court. He moved to London along with the court in 1603, at the time of the Union of Crowns, and remained in London until he died in 1624. He had married twice but had no recognised children surviving at the time of his death, and he left the bulk of his estate to found a hospital to care for "faitherless bairns" (orphaned children) in his home city.