There are 142 Fast Food Restaurants in Washington County, Oregon, serving a population of 572,071 people in an area of 725 square miles. There is 1 Fast Food Restaurant per 4,028 people, and 1 Fast Food Restaurant per 5 square miles.
In Oregon, Washington County is ranked 34th of 36 counties in Fast Food Restaurants per capita, and 2nd of 36 counties in Fast Food Restaurants per square mile.