RapidRide is a network of limited-stop bus routes with some bus rapid transit features in King County, Washington, operated by King County Metro. The network consists of seven routes totaling 76 miles (122 km) that carried riders on approximately 64,860 trips on an average weekday in 2016, comprising about 17 percent of King County Metro's total daily ridership.

King County Metro, officially the King County Metro Transit Department and often shortened to Metro, is the public transit authority of King County, Washington, which includes the city of Seattle. It is the eighth-largest transit bus agency in the United States. In 2023, the system had a ridership of 78,121,600, or about 256,200 per weekday as of the fourth quarter of 2023. Metro employs 2,444 full-time and part-time operators and operates 1,540 buses.