ZIP code 59640 is officially located in the state of Montana, primarily serving the city of Marysville. It falls under the administrative jurisdiction of Lewis and Clark County. When planning mail delivery, logistics routing, or demographic research, 59640 operates within the Mountain Time (MT) timezone and supports the 255 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 59640 ZIP Code Tabulation Area is approximately 30,355. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $120,640.