GO Transit bus services are provided throughout the Greater Toronto and Hamilton Area and the Greater Golden Horseshoe. In 2023, the system had a ridership of 15,229,800.

GO Transit is a regional public transit system serving the Greater Golden Horseshoe region of Ontario, Canada. With its hub at Union Station in Toronto, GO Transit's green-and-white trains and buses serve a population of more than seven million across an area over 11,000 square kilometres (4,200 sq mi) stretching from Kitchener in the west to Peterborough in the east, and from Barrie in the north to Niagara Falls in the south. In 2023, the system had a ridership of 56,036,900. GO Transit operates diesel-powered double-decker trains and coach buses, on routes that connect with all local and some long-distance inter-city transit services in its service area.