State Route 6 (SR 6) is a 51.37-mile (82.67 km) long state highway in Pacific and Lewis counties in the U.S. state of Washington. The highway, which extends from U.S. Route 101 (US 101) in Raymond east to Interstate 5 (I-5), co-signed with US 12, in Chehalis. Major communities located on the highway include Raymond, Pe Ell, Adna and Chehalis. The first state highway that used the current route of SR 6 was State Road 19, established in 1913. State Road 19 became State Road 12 in 1923, which became Primary State Highway 12 (PSH 12) in 1937. In 1964, PSH 12 became SR 6 and since, three minor construction projects have been arranged, only two have been completed.

Pacific County is a county in the U.S. state of Washington. As of the 2020 census, the population was 23,365. Its county seat is South Bend, and its largest city is Raymond. The county was formed by the government of Oregon Territory in February 1851 and is named for the Pacific Ocean.