Pomeroy is a city in Garfield County, Washington, United States. The population was 1,425 at the 2010 census. It is the county seat of Garfield County.
Pomeroy is located at 46°28′24″N 117°35′53″W / 46.47333°N 117.59806°W / 46.47333; -117.59806 (46.473334, -117.598119).
According to the United States Census Bureau, the city has a total area of 1.8 square miles (4.6 km²), all of it land.