Bay Street is a street in downtown Toronto, Ontario Canada. It is the centre of Toronto's financial district and is often used as a synonym for Canada's financial industry just as Wall Street is used in the United States.

Canada's economic life is dominated by five large national banks. Four of those banks have their de facto headquarters at the corner of King and Bay. The fifth bank is located one block south. The Bank of Montreal complex also includes the Toronto Stock Exchange, Canada's largest stock exchange.

The legal headquarters of three of the banks are located elsewhere in Canada — in Montreal, Quebec and Halifax, Nova Scotia. The banks all operate under federal charters and their location is controlled by the federal Minister of Finance . It would cause a major political furor if the federal government allowed the banks to transfer the official headquarters and their attached jobs from the Maritimes, the poorest region of Canada, or Quebec, because of its separatist politics, to much-hated Toronto . However, everyone in Canada understands where the decisions get made.

Because of the presence of the banks and the stock exchange, the area is home to numerous corporate headquarters, high-powered legal firms, insurance companies and stock brokers. In turn, the presence of so many decision-makers has brought in advertising agencies and marketing companies. The banks have built large office towers, much of whose space is leased to these companies. The bank towers, and much else in Toronto's core, are connected by underground walkways lined with retail establishments making the area one of the most important shopping districts in Toronto. Note that the stores are only open during weekdays when the financial district is populated. During the weekend, the area is deserted and the stores are closed.

It is estimated that 100,000 commuters enter and leave the financial district each working day. Transportation links are centred on Toronto's Union Station at the south end of the financial district. Union Station is the hub of the GO Transit system that provides rail and bus links to Toronto's suburbs. It is also a station on the subway system.