Columbia County ZIP Codes

List of ZIP Codes in Columbia County

The following table lists ZIP Codes associated with Columbia County, Washington, based on ZIP Code Tabulation Area (ZCTA) data from the U.S. Census Bureau.


S.N. Zip Code Latitude Longitude City Population Density
1 99328 46.26937 -117.87956 Dayton 3,595 2.1
2 99359 46.53325 -118.15697 Starbuck 107 1.0


About Columbia County ZIP Codes

Columbia County in Washington (WA) is served by approximately 2 ZIP Codes. These codes cover residential neighborhoods, business districts, and rural areas that fall under the county's jurisdiction.

Based on ZIP-level population estimates, the total population covered by these ZIP Codes is around 3,702 people. Population and density values vary from one ZIP Code to another, reflecting the mix of dense urban communities and lower-density suburban or rural zones.

Many of the most significant population centers in Columbia County are located in cities such as Dayton, Starbuck. These cities and towns help define the economic and demographic character of the county.

Most ZIP Codes in Columbia County, Washington follow the America/Los_Angeles time zone.