Colsterworth is a village and civil parish in the South Kesteven district of Lincolnshire, England, less than half a mile west of the A1, about 7 miles south of Grantham, and 12 miles north-west of Stamford. The village with the hamlet of Woolsthorpe-by-Colsterworth had a recorded population of 1,713 at the time of the 2011 census, in an area of 1,465 hectares.