The state of Oregon is divided into 36 counties. Clackamas County is the oldest (founded in 1843), while Deschutes County is the youngest (established in 1916).

Multnomah County is the most populous, with a population of 790,670 people. Harney County has the largest land area (26,250 km2) while Multnomah County has the smallest (1,127 km2).

Please find a list of all Oregon counties listed alphabetically below.

• Baker County, OR
• Benton County, OR
• Clackamas County, OR
• Clatsop County, OR
• Columbia County, OR
• Coos County, OR
• Crook County, OR
• Curry County, OR
• Deschutes County, OR
• Douglas County, OR
• Gilliam County, OR
• Grant County, OR
• Harney County, OR
• Hood River County, OR
• Jackson County, OR
• Jefferson County, OR
• Josephine County, OR
• Klamath County, OR
• Lake County, OR
• Lane County, OR
• Lincoln County, OR
• Linn County, OR
• Malheur County, OR
• Marion County, OR
• Morrow County, OR
• Multnomah County, OR
• Polk County, OR
• Sherman County, OR
• Tillamook County, OR
• Umatilla County, OR
• Union County, OR
• Wallowa County, OR
• Wasco County, OR
• Washington County, OR
• Wheeler County, OR
• Yamhill County, OR