ZIP code 99136 is officially located in the state of Washington, primarily serving the city of Hay. It falls under the administrative jurisdiction of Whitman County. When planning mail delivery, logistics routing, or demographic research, 99136 operates within the Pacific Time (PT) timezone and supports the 869 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 99136 ZIP Code Tabulation Area is approximately 34,469. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $52,136.