In Benton County, Washington the Kennewick post office has the maximum zip codes – 99336, 99338 and 99337. There are 6 other post offices in this County – Benton City, Prosser, Paterson, Richland, Plymouth and West Richland. In Chelan County Wenatchee post office has the maximum zip codes – 98801 and 98807.
Washington Zip Codes Map befor March 17, 2016
Last Updated Date: August 12, 2016