South Bend is a city in Pacific County, Washington, United States. It is the county seat of Pacific County. The population was 1,637 as of the 2010 census. The town is widely-known for its oyster production and scenery.

South Bend was officially incorporated on September 27, 1890. The state of the city comes from its location on the Willapa River. The county chair was relocated from Oysterville to South Bend in 1893. The Pacific County Courthouse is upon the National Register of Historic Places. The archaic South Bend Courthouse was the site of the first and only endowment carried out in Pacific County, when convicted murderer Lum You was hanged in 1902.

South Bend is located at 46°39′49″N 123°48′4″W / 46.66361°N 123.80111°W / 46.66361; -123.80111 (46.663477, -123.801176) on the Willapa river.

According to the United States Census Bureau, the city has a total area of 2.01 square miles (5.21 km²), of which, 1.63 square miles (4.22 km²) is house and 0.38 square miles (0.98 km²) is water.

As of the census of 2010, there were 1,637 people, 684 households, and 414 families animate in the city. The population density was 1,004.3 inhabitants per square mile (387.8/km²). There were 780 housing units at an average density of 478.5 per square mile (184.7/km²). The racial makeup of the city was 72.2% White, 0.2% African American, 3.4% Native American, 5.5% Asian, 13.3% from supplementary races, and 5.4% from two or more races. Hispanic or Latino of any race were 19.4% of the population.