Bank of Montreal (lang-fr|Banque de Montréal), (commonly BMO in either official language), or BMO Financial Group, is one of the Big Five banks in Toronto. The Bank of Montreal officially opened its doors for business on November 3, 1817. It was founded by John Richardson and eight merchants in a rented house in Montreal, Quebec. On June 23, 1817 the Articles of Association were signed, making it Canada's oldest bank. BMO's Institution Number (or bank number) is 001.  Wikipedia