The ORCA card is a contactless, stored-value smart card system for public transit in the Puget Sound region of Washington, United States. The card is valid on most transit systems in the Seattle metropolitan area, including Sound Transit, local bus agencies, Washington State Ferries, the King County Water Taxi, and Kitsap Fast Ferries. It was launched in 2009 and is managed by the Central Puget Sound Regional Fare Coordination Project, a board composed of local transit agencies.

Sound Transit (ST), officially the Central Puget Sound Regional Transit Authority, is a public transit agency serving the Seattle metropolitan area in the U.S. state of Washington. It operates the Link light rail system in Seattle and Tacoma, regional Sounder commuter rail, and Sound Transit Express bus service. The agency also coordinates the regional ORCA fare card system, which is also used by local transit operators. In 2019, Sound Transit services carried a total of 48 million passengers and averaged over 161,000 riders on weekdays.