Hastings—Frontenac—Lennox and Addington was a federal and provincial electoral district in Ontario, Canada, that was represented in the House of Commons of Canada from 1984 to 2003, and in the Legislative Assembly of Ontario from 1999 to 2007.
The federal riding was created in 1976 when Hastings—Frontenac was renamed. The riding initially consisted of:
that part of the County of Frontenac including and lying northerly of the Townships of Portland, Loughborough, Storrington and Pittsburg, but excluding the southwest part of the Township of Pittsburg;
that part of the County of Hastings including and lying northerly of the Townships of Marmora, Madoc and Elzevir;
the County of Lennox and Addington, but excluding the Township of Armherst Island.
In 1987, the riding was re-defined to consist of:
that part of the County of Frontenac including and lying northerly of the Townships of Portland, Loughborough, Storrington and Pittsburg, but excluding the southwest part of the Township of Pittsburg;
the County of Lennox and Addington but excluding the Township of Armherst Island;
that part of the County of Hastings lying northerly of the southerly boundary of the townships of Hungerford, Huntingdon and Rawdon and the southerly limit of the Village of Stirling.
In 1996, the riding was re-defined to consist of:
the County of Frontenac, excepting the City of Kingston, the townships of Howe Island, Kingston and Wolfe Island, and that part of the Township of Pittsburgh lying south of the Macdonald-Cartier Freeway;
the County of Lennox and Addington;
that part of the County of Hastings lying northerly of the southerly boundary of the townships of Hungerford, Huntingdon and Rawdon, and the southerly limit of the Village of Stirling.