He married twice: Firstly on 6 December 1726, to
Lady Elizabeth Sackville (d.1729), a daughter of
Lionel Sackville, 1st Duke of Dorset. Secondly he married
Lady Louisa Carteret (c.1712–1736), a daughter of
John Carteret, 2nd Earl Granville and a co-heiress of her childless brother
Robert Carteret, 3rd Earl Granville (1721–1776). On her father's side she was a great-grand-daughter of
John Granville, 1st Earl of Bath (1628–1701), and her father's first-cousin was
William Granville, 3rd Earl of Bath (1692–1711), on whose death the
Earldom of Bath became extinct. The title of
Marquess of Bath was later created for her eldest son in 1789 (see below), the title
Earl of Bath being then unavailable as it had been recreated for a member of the Pulteney family. Her grandmother
Frances Thynne was the daughter of
Thomas Thynne, 1st Viscount Weymouth. When Lady Louisa died in childbirth, in her early twenties, her friend,
Mrs Delany, wrote:"Her husband's ... loss is irreparable." During her illness, Mrs Delany had written that "my Lord Weymouth is like a madman". By Louisa Carteret he had two sons: he changed his name and arms to Carteret, in compliance with his inheritance from his childless uncle
Robert Carteret, 3rd Earl Granville, 3rd Baron Carteret (1721–1776) (under the terms of the will of the latter's father
John Carteret, 2nd Earl Granville, 2nd Baron Carteret (1690–1763), of his estates including
Hawnes Park (now
Haynes Park), in Bedfordshire and
Stowe House,
Kilkhampton in Cornwall (the ancient seat of the Granvilles,
Earls of Bath). He also succeeded him as
Bailiff of Jersey, a post (for life) long held by heads of the Carteret family. In 1784 he was created Baron Carteret, of Hawnes, thus reviving his uncle's second title. ==Death and burial==