Prior to 1952, Peterborough was split into two ridings, one of which was sometimes partly joined to neighbouring Hastings County.

Since 1999, the riding boundaries and names of the provincial and federal electoral districts have been identical.

It consisted initially of the city of Peterborough and the townships of Galway, Cavendish, Harvey, Ennismore, Smith, Douro, Otonabee, and North Monaghan.

[5] Following the 2022 Canadian federal electoral redistribution, this riding will be renamed Peterborough at the first election held after approximately April 2024.

According to the 2021 Canadian census[7] Ethnic groups: 86.6% White, 6.3% Indigenous, 2.3% South Asian, 1.1% Black Languages: 91.6% English Religions: 52.8% Christian (20.3% Catholic, 9.4% United Church, 6.3% Anglican, 1.7% Presbyterian, 1.4% Pentecostal, 1.3% Baptist, 12.4% Other), 1.1% Muslim, 1.0% Hindu, 43.0% None Median income: $38,800 (2020) Average income: $49,640 (2020) This riding has elected the following members of Parliament: