North Plains is a city in Washington County, Oregon, United States, off U.S. 26 on the northwest outskirts of the Portland metropolitan area.

[5] The area to be known as the city of North Plains was platted in September 1910 by the Ruth Trust Company of Portland.

They purchased area tracts after James J. Hill planned to extend United Railways there.

[6][7] On June 25, 1963, North Plains voted 90 to 56 to incorporate as a city; at the time the population was around 500.

David Duval won the Nike Tour Championship there in 1993, and it was home to the U.S. Women's Open in 1997 and 2003.

[8] Horning's Hideout within the North Plains area was home to Faerieworlds Festival 2004.

[10] According to the United States Census Bureau, the city has an area of 0.90 square miles (2.33 km2), all land.

On a percentage basis, North Plains is among the top 100 locations (with at least 500 residents) home to Panamanian Americans.