is a borough in Northampton County, Pennsylvania, United States. Incorporated in 1909, Walnutport is located in the Lehigh Valley region of Pennsylvania along the Lehigh River.
The population of Walnutport was 2,043 at the 2000 census. The U.S. postal code (zip code) for Walnutport, PA is 18088.
According to the United States Census Bureau, the borough has a total area of 0.8 square miles (2.1 km²), of which, 0.8 square miles (1.9 km²) of it is land and 0.1 square miles (0.2 km²) of it (7.41%) is water.
Walnutport is located 15 miles north of Allentown at the intersections of Pennsylvania Route 145 and Mountain View Drive, an extension of State Route 946. It's also located 4 miles south of Palmerton.