Grantham Killingworth (1699–1778) was an English lay Baptist controversialist.
A grandson of Thomas Grantham, he was born in Norwich.
He was a layman, and a personal friend of William Whiston, whom he supplied with evidence of cures effected through "prayer, fasting, and annointing with oyl" by a Unitarian Baptist minister, William Barron (died 7 February 1731, aged 51).
[1][2] Killingworth died in 1778, leaving an endowment to the Priory Yard General Baptist chapel, in Norwich.
[1] Killingworth wrote on the perpetuity of baptism, against Thomas Emlyn; in favour of adult baptism, against John Taylor, and Michajah Towgood; and on close communion, against James Foster, John Wiche, and Charles Bulkley.