Toronto Pearson Airport Lost & Found - Official site and online file reporting
Items may be held at the police booths, information desks near international arrivals at both T1 or T3 before transporting to the airport Lost & Found office or various government agency offices
Something lost in the last hour or two may be still at T3 info desk. Lost items are transported from T3 to T1 Lost & Found on a daily basis
Passports (all countries) are transferred to Canada Border Services Agency
Nexus Cards found at the airport are transferred into the Nexus office at T1 Departures
Items lost on an airplane, including lost luggage, please contact the airline. Full list of airlines and contacts.
Items lost on Air Canada premises (planes, AC Lounges), see Air Canada Lost & Found, T1 Domestic Arrivals & Baggage Hall
Items lost on UP Express Train, file report at https://www.upexpress.com/CustomerSupport/LostFound
For all other items lost in the terminals, inter-terminal Link Train or parking garages, see Airport Lost & Found