ZIP code 61911 is officially located in the state of Illinois, primarily serving the city of Arthur. It falls under the administrative jurisdiction of Douglas County. When planning mail delivery, logistics routing, or demographic research, 61911 operates within the Central Time (CT) timezone and supports the 243 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 61911 ZIP Code Tabulation Area is approximately 38,043. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $127,911.