San Francisco, CA SFO to Toronto, ON YTO flight with United

United Airlines, established in 1926, is a major U.S. airline headquartered in Chicago, Illinois. Operating an extensive domestic and international network, United serves more destinations than any other airline, connecting travelers across six continents. The airline's eight hubs include Chicago–O'Hare, Denver, Houston–Intercontinental, Los Angeles, Newark, San Francisco, Washington–Dulles, and Guam. As a founding member of the Star Alliance, United offers a comprehensive range of services, including regional flights through United Express, catering to both leisure and business travelers. The airline is committed to sustainability, investing in sustainable aviation fuel and innovative technologies to reduce its environmental impact.

Air Canada is Canada's largest airline and flag carrier, headquartered in Saint-Laurent, Quebec. Founded in 1937 as Trans-Canada Air Lines, it was renamed Air Canada in 1964 and fully privatized in 1989. As a founding member of Star Alliance, Air Canada provides scheduled passenger and cargo services to over 220 destinations across six continents. The airline operates a diverse fleet, including Airbus A320 family aircraft, Boeing 737 MAX, Boeing 777, and Boeing 787 Dreamliner for both short and long-haul routes. Air Canada also offers leisure travel packages through its subsidiary, Air Canada Vacations.