Howorth was unmarried but left a bequest to four illegitimate children born of Mary Chippendale.[2] He was succeeded as MP for Abingdon by Edward Loveden Loveden.
^Drummond, Mary M. (1964). "MAYOR, John (c.1735-1817), of Lacy Court, nr. Abingdon, Berks". In Namier, L.; Brooke, J. (eds.). The History of Parliament: the House of Commons 1754-1790. Retrieved 19 February 2019 – via History of Parliament Online.