| Northumberland—Peterborough South | |
| Province: | Ontario |
| Fed-Status: | active |
| Fed-District-Number: | 35071 |
| Fed-Created: | 2013 |
| Fed-Election-First: | 2015 |
| Fed-Election-Last: | 2021 |
| Fed-Rep: | Philip Lawrence |
| Fed-Rep-Party: | Conservative |
| Demo-Pop-Ref: | [1] |
| Demo-Census-Date: | 2011 |
| Demo-Pop: | 107840 |
| Demo-Electors: | 88276 |
| Demo-Electors-Date: | 2015 |
| Demo-Area: | 3001 |
| Demo-Cd: | Durham, Northumberland, Peterborough County |
| Demo-Csd: | Alnwick/Haldimand, Brighton, Clarington, Cobourg, Cramahe, Hamilton Township, Otonabee–South Monaghan, Peterborough, Port Hope, Trent Hills |
Northumberland—Peterborough South (French: '''Northumberland—Peterborough-Sud''') is a federal electoral district in Ontario.
Northumberland—Peterborough South was created by the 2012 federal electoral boundaries redistribution and was legally defined in the 2013 representation order. It came into effect upon the call of the 42nd Canadian federal election, scheduled for 19 October 2015. 77% of the riding was formed from Northumberland—Quinte West, 13% from Durham and 10% from Peterborough.
The riding was originally intended to be named Northumberland—Pine Ridge.[2]
Under the 2022 Canadian federal electoral redistribution the riding will be renamed Northumberland—Clarke at the next federal election.[3]
The riding is located in Central Ontario along Lake Ontario. It contains the entirety of Northumberland County, southern Peterborough and the eastern half of the municipality of Clarington.
According to the 2021 Canadian census[4]
Ethnic groups: 89.8% White, 5.1% Indigenous, 1.2% Black, 1.1% South Asian
Languages: 92.6% English, 1.3% French
Religions: 54.1% Christian (17.6% Catholic, 11.3% United Church, 7.6% Anglican, 2.4% Presbyterian, 1.8% Baptist, 1.2% Pentecostal, 12.2% Other), 43.8% None
Median income: $41,600 (2020)
Average income: $53,100 (2020)
This riding has elected the following members of Parliament:
| 2021 federal election redistributed results[5] | |||||
|---|---|---|---|---|---|
| Party | Vote | % | |||
| 27,553 | 43.99 | ||||
| 21,311 | 34.02 | ||||
| 8,735 | 13.95 | ||||
| 3,430 | 5.48 | ||||
| 1,608 | 2.57 | ||||
| 2011 federal election redistributed results[6] | |||||
|---|---|---|---|---|---|
| Party | Vote | % | |||
| 29,377 | 53.37 | ||||
| 11,611 | 21.09 | ||||
| 11,331 | 20.58 | ||||
| 2,576 | 4.68 | ||||
| Others | 154 | 0.28 | |||