The Massachusetts Bay Transportation Authority is the public agency responsible for operating most public transportation services in Greater Boston, Massachusetts. The MBTA transit network includes the MBTA subway with three metro lines, two light rail lines, and a five-line bus rapid transit system ; MBTA bus local and express service; the twelve-line MBTA Commuter Rail system, and several ferry routes. In 2023, the system had a ridership of 239,981,700, or about 812,400 per weekday as of the third quarter of 2024, of which the rapid transit lines averaged 267,700 and the light rail lines 102,500, making it the fourth-busiest rapid transit system and the third-busiest light rail system in the United States. As of the third quarter of 2024, average weekday ridership of the commuter rail system was 109,300, making it the fifth-busiest commuter rail system in the U.S.
