U.S. Customs and Border Protection (USCBP) temporarily halted operations at Montréal-Trudeau International Airport on July 29, 2026, triggering the cancellation of approximately 20 flights bound for the United States.
The suspension was caused by a strong varnish odour emanating from painting work associated with the airport’s ongoing $10-billion redevelopment project. The odour originated from construction materials at the site.
The Montreal Fire Department inspected the affected area and confirmed that the odour posed no health risk. Airport authorities increased ventilation efforts to mitigate the presence of the odour within the customs processing zone.
Airport officials indicated efforts are underway to
restore USCBP operations as swiftly as possible. They reported that customs processing is gradually resuming but warned passengers to anticipate delays. Passengers were also advised to contact USCBP directly for inquiries related to U.S. preclearance procedures.
Passengers traveling to the United States were encouraged to verify their flight status with airlines prior to arriving at the airport, as delays and cancellations may continue while operations normalize.
The redevelopment effort represents one of the largest infrastructure transformation projects in Montréal-Trudeau International Airport’s history, with construction activities expected to continue over the next decade.
