{"id":8612,"date":"2023-10-02T20:09:14","date_gmt":"2023-10-02T20:09:14","guid":{"rendered":"https:\/\/townsvillages.com\/us\/?p=8612"},"modified":"2026-08-14T22:20:50","modified_gmt":"2026-08-14T22:20:50","slug":"columbia-county-washington","status":"publish","type":"post","link":"https:\/\/townsvillages.com\/us\/columbia-county-washington\/","title":{"rendered":"Columbia County, Washington"},"content":{"rendered":"

Columbia County is a county in Washington, United States, on the Palouse prairie of the state’s southeastern corner. It had a population of 3,952 at the 2020 census and covers 873 square miles (2,260 km2) centred near 46\u00b018\u2032N 117\u00b055\u2032W, of which 869 square miles is land and 4.9 square miles is water.<\/p>\n

Dayton is the county seat and its postal code is 99328. The county has one city, one town, and a handful of unincorporated communities, and sits in the Pacific time zone.<\/p>\n

Towns & Villages in Columbia County<\/h2>\n

Columbia County has just two incorporated places — Dayton and Starbuck — and a scatter of unincorporated communities and rural place names left from its wheat-farming and railroad past. The table below marks incorporated status; most of the smaller names are historic sidings, ranch clusters, or crossroads rather than active settlements.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n\n
Place<\/th>\nType<\/th>\nPop.<\/th>\nZIP<\/th>\n<\/tr>\n<\/thead>\n
Dayton<\/td>\nCity · seat<\/td>\n2,448<\/td>\n99328<\/td>\n<\/tr>\n
Starbuck<\/td>\nTown<\/td>\n—<\/td>\n99359<\/td>\n<\/tr>\n
Covello<\/td>\nUnincorp.<\/td>\n—<\/td>\n99328<\/td>\n<\/tr>\n
Huntsville<\/td>\nUnincorp.<\/td>\n—<\/td>\n99328<\/td>\n<\/tr>\n
Jackson<\/td>\nUnincorp.<\/td>\n—<\/td>\n99328<\/td>\n<\/tr>\n
Marengo<\/td>\nUnincorp.<\/td>\n—<\/td>\n99328<\/td>\n<\/tr>\n
Turner<\/td>\nUnincorp.<\/td>\n—<\/td>\n99328<\/td>\n<\/tr>\n
Grange City<\/td>\nUnincorp. (ghost town)<\/td>\n—<\/td>\n—<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Several names on the old list — Alto, Baileysburg, Delaney, Dumas, Long, McKay, Menoken, Mountain Home Park, Mountain Top, Patit, Powers, Relief, Ronan, Tucannon, Varna, and Whetstone — are ranch, canyon, or creek names on USGS maps rather than verifiable populated places; they are omitted here pending a source that can confirm them as settlements.<\/p>\n

ZIP Codes<\/h2>\n