It consisted of: (a) the county of Lennox and Addington (excluding the townships of Ernestown, Fredericksburg North and Fredericksburg South, Richmond, Adolphustown, and Amherst Island); (b) the county of Frontenac (excluding the city of Kingston and the townships of Kingston, Storrington, Pittsburgh, Howe Island, Wolfe Island (including Simcoe Island, Horse Shoe Island and Mud Island)); and (c) the part of county of Peterborough lying east of and including the townships of Anstruther, Burleigh, Dummer and Asphodel; and (d) the part of county of Hastings lying north of and including the townships of Rawdon, Huntingdon, Madoc and Elzevir.

The electoral district was abolished in 1966 when it was redistributed between Frontenac—Lennox and Addington, Hastings, Peterborough and Victoria—Haliburton ridings.

Hastings—Frontenac was re-created in 1976 from parts of Frontenac—Lennox and Addington, Hastings, and Victoria—Haliburton ridings.

The new riding consisted of: (a) the part of the County of Frontenac including and lying north of the Townships of Portland, Loughborough, Storrington and Pittsburg, but excluding the southwest part of the Township of Pittsburg; (b) the part of the County of Hastings including and lying north of the Townships of Marmora, Madoc and Elzevir; and (c) the County of Lennox and Addington, but excluding the Township of Armherst Island.

This riding has elected the following members of Parliament: On Mr. Smith's death, 17 March 1959: