ZIP code 03603 is officially located in the state of New hampshire, primarily serving the city of Charlestown. It falls under the administrative jurisdiction of Sullivan County. When planning mail delivery, logistics routing, or demographic research, 03603 operates within the Eastern Time (ET) timezone and supports the 847 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 03603 ZIP Code Tabulation Area is approximately 19,047. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $91,603.