Neville, who was illegitimate, had at least three brothers: Nicholas de Neville, a canon at Chichester Cathedral; William de Neville, treasurer of the see of Chichester; and Robert de Neville, holder of a prebend at Chichester. The identity of their father is unknown, but another likely sibling was Roger, who held land in Lincolnshire. Robert became Chancellor of the Exchequer, and Nicholas a baron of the Exchequer. Ralph Neville was also related to Hugh de Neville, King John of England's chief forester.