Sir Nicholas Bonsor was the elder son of Sir Bryan Bonsor (1916–1977) and his wife Elizabeth Hambro (1920–1995). In 1969, he married Hon. Nadine Marisa Lampson, now the Hon. Lady Bonsor, a daughter of Graham Curtis Lampson, 2nd
Baron Killearn. They had five children, including Sir Alexander Cosmo Walrond Bonsor (b. 1976) and entrepreneur Mary Bonsor (b. 1987). Bonsor died on 21 March 2023, at the age of 80. His eldest son Alexander succeeded to the baronetcy as the 5th Baronet. ==Notes==