Southwick is a small village and civil parish in Northamptonshire, England. It is approximately 3 miles (4.8 km) north of the town of Oundle and is set in a valley of the River Nene. The village lies in the North Northamptonshire. Before local government changes in 2021 it fell within the non-metropolitan district of East Northamptonshire, which lay within the East Midlands region. At the time of the 2001 census, the parish's population was 180 people, increasing marginally to 181 at the 2011 Census.