U.S. Customs and Border Protection (USCBP) temporarily suspended operations at Montréal-Trudeau International Airport on July 29, 2026, due to a strong odour identified as varnish from painting work near the customs area. The Montreal Fire Department inspected the site and confirmed the odour posed no health risk.
Cancellation of Around 20 U.S.-Bound Flights
The suspension led to the cancellation of around 20 U.S.-bound flights requiring customs preclearance at Montréal-Trudeau Airport. Passengers experienced delays and cancellations affecting flights to the United States on that day.
Official Statements and Passenger Advisories
Airport officials stated every effort was being made to restore U.S. Customs operations quickly. A statement on the YUL Aéroport International Montréal-Trudeau
website explained that while the varnish odour was unpleasant, it posed no health risk, and thanked passengers for their patience. Travellers heading to the U.S. were urged to check flight status with their airline before travelling to the airport.
Resumption and Ventilation Measures
Ventilation in the affected customs area was increased to address the odour. USCBP operations were gradually resuming following the suspension, although delays remained possible as operations normalized.
Airport Redevelopment and Infrastructure Context
Montréal-Trudeau International Airport is undergoing a $10-billion redevelopment project, one of the largest infrastructure transformations in its history, with major construction expected to continue over the next decade. The odour originated from construction materials
associated with this work near the customs area.
