ZIP code 98570 is officially located in the state of Washington, primarily serving the city of Onalaska. It falls under the administrative jurisdiction of Lewis County. When planning mail delivery, logistics routing, or demographic research, 98570 operates within the Pacific Time (PT) timezone and supports the 534 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 98570 ZIP Code Tabulation Area is approximately 5,434. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $130,570.