Garfield County is a county located in the U.S. state of Washington. As of the 2020 census, the population was 2,286, making it the least populous county in Washington; with about 3.2 inhabitants per square mile (1.2/km2), it is also the least densely populated county in Washington. The county seat and only city is Pomeroy.

Pomeroy is a city in Garfield County, Washington, United States. The population was 1,389 at the 2020 census. It is the county seat of and only incorporated city in Garfield County.