Formed July 5, 1843 (4th county)
Yamhill County (107,721), McMinnville (34,332)
The Modern style brown brick structure replaced the 1888 version of the courthouse. The courthouse is on 5th Street at Evans Street. Oregon State Highway 99 West is three blocks west of the facility. Roald, Schmeer and Harrington designed the 1964 courthouse. An old 1937 Post Office converted into Clerk’s Office and a converted house to Commissioners Building support the courthouse. The county was established on July 5, 1843 as one of the original counties (4th county.) It is named for one of the local Native American tribes. The county seat was originally at Lafayette until 1889. McMinnville is named for McMinnville, Tennessee.
Yamhill County government consists of a treasurer, a sheriff, an attorney, an administrator, and a clerk (executive). It has 3 Commissioners (legislative.) Four District Court Judges serve Yamhill County (judicial.) The county is in the northwest part of the state. Portland, Oregon is northeast and Eugene, Oregon is southeast of the county. The county center is 2.3 miles North of McMinnville. The county is surrounded clockwise by Washington, Clackamas, Marion, Polk, and Tillamook counties.
The area of the county is 716 square miles. It is 32 out of 36 in the state. It ranks 10 out of 36 in population in the state. It has a density of 150.4 persons per square mile making it 5 out of 36 in the state. Yamhill County has 76.9% of its population in its incorporated areas. There are no Interstates or United States Highways in the county. Yamhill County is shaped like a capital letter J. McMinnville is located in the southeast quarter of the county. McMinnville is the county seat and the largest city. It is 31.9% of the county population. This county is in the Portland-Vancouver-Beaverton Metropolitan Statistical Area.
Amity
Carlton
Dayton
Dundee
Lafayette
McMinnville
Newberg
Sheridan
Yamhill
Willamania