ZIP code 48191 is officially located in the state of Michigan, primarily serving the city of Willis. It falls under the administrative jurisdiction of Washtenaw County. When planning mail delivery, logistics routing, or demographic research, 48191 operates within the Eastern Time (ET) timezone and supports the 754 area codes.
According to the latest US Census Bureau and American Community Survey (ACS) datasets, the total population residing within the 48191 ZIP Code Tabulation Area is approximately 16,154. Understanding local economics is critical for market analysis; the median household income in this postal area sits at $87,191.