Milton is a borough in Northumberland County, Pennsylvania, on the Susquehanna River, 50 miles (80 km) north of Harrisburg. Settled in 1770, it was incorporated in 1817, and is governed by a charter that was revised in 1890. Formerly, its extensive manufacturing plants included car and woodworking machinery shops, rolling, flour, knitting, planing, and saw mills; washer, nut, and bolt works; and furniture, shoe, couch, nail, fly net, bamboo novelty, and paper-box factories. In 1900, 6,175 people lived in Milton. In 1940, 8,313 people lived here. The population was 6,650 at the 2000 census.
Milton is located at 41°1′3″N 76°51′3″W / 41.0175°N 76.85083°W / 41.0175; -76.85083 (41.017413, -76.850758).
According to the United States Census Bureau, the borough has a total area of 3.8 square miles (9.7 km²), of which, 3.5 square miles (9.0 km²) of it is land and 0.3 square miles (0.8 km²) of it (7.73%) is water.