In 1846 Hildyard entered political life as the Conservative Member of Parliament for the southern division of Nottinghamshire. It was a toughly contested election. Hildyard was supported, according to the University of Nottingham, by the 4th Duke of Newcastle under Lyme "in spite of the fact that Newcastle's son, the Earl of Lincoln, was his opponent. Lincoln attacked Hildyard's youth and inexperience, but the 'young squire' still defeated him by a majority of almost 700. Hildyard held South Nottinghamshire from 1846 until 1852. He was re-elected in 1866. He then continued to represent the South Nottinghamshire constituency until his retirement in 1885."