The son of William Elliot of Wells (1660-1728, known to posterity as the "Laceman", from his trade in gold-embroidered lace from which he made his fortune) and his wife Eleanor née Tankard, the younger William was christened 6 March 1701–2 at St James's Church, Piccadilly, Westminster. Around 1720, he stood as legal guardian to Granville Elliott, the infant son of his elder sister Charlotte Elliot and her recently deceased husband Roger Elliott.
William, the son of William Elliot of Wells (1660-1728, known as "the Laceman" due to his trade in gold-embroidered lace that brought him wealth), was baptized on March 6, 1701–2 at St James's Church, Piccadilly, Westminster. Around 1720, he acted as a legal guardian for Granville Elliott, the infant son of Charlotte Elliot and her late husband Roger Elliott.