Foster, Washington was a former community, north of the urban center of today's Tukwila, in King County in the U.S. state of Washington. At one time, it had a post office and a school. In the 19th century, there was a Foster Ferry Landing on the Duwamish River near where today South 56th Street crosses the river and the Green River Trail. The name lingers on in the Foster Golf Links immediately upstream of that point and in Joseph Foster Memorial Park about 0.25 miles (0.40 km) to the south-southwest.