ZIP code 99371 is officially located in the state of Washington, primarily serving the city of Washtucna. It falls under the administrative jurisdiction of Adams County. When planning mail delivery, logistics routing, or demographic research, 99371 operates within the Pacific Time (PT) timezone and supports the 585 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 99371 ZIP Code Tabulation Area is approximately 39,085. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $47,371.