Bus companies generally listed in the July 1942 Russell's Guide or the 1952 Mass Transportation's Directory, and their predecessor and successor companies. This list is somewhat arbitrary and provides a general overview. Some available beginning dates are from early reports of the Washington Department of Public Works, indicating a Certificate of Convenience and Necessity.
Washington Coast Lines - operated until 1983 (to Grays Harbor Transportation Authority)
Original route: Olympia-Aberdeen-South Bend/Moclips
Prior to 1947 was Grays Harbor Lines
1947-1957 was Blue-Gray Stages
1957-1967 was Harbor Lines
1967-1969 was Grays Harbor Lines
Bremerton-Tacoma Stages - operated until 1987
Original route: Bremerton-Tacoma
Trailways member (Cascade Trailways) after 1975
After 1979 was Cascade Trailways
After 1987 changed routes focus
Consolidated Transportation Co. - operated until 1947 (to Blue-Gray Stages later Washington Coast Lines/above)
Original route: Astoria OR-Long Beach-Chehalis
1944-1947 was Seashore Bus Line
Everett-Arlington Stage - operated 1921-1948
Original route: Everett-Arlington-Darrington
Lake Shore Stage Line - operated until 1943
Operated various directions from Tacoma
Port Townsend-Southern Stages - operated 1947-1953
Original route: Quilcene-Port Townsend
Trailways member (Olympic Trailways) 1949-1953
Ryderwood-Chehalis Stages - operated until 1949
Original route: Ryderwood-Chehalis
Shelton Auto Transportation Co. - operated 1921-1944 (to Bremerton-Tacoma Stages/above)
Original route: Olympia-Shelton-Bremerton
Spokane-Priest Lake Motor Coach Lines - operated until 1949
Original route: Spokane-Newport-Priest River ID