On July 29, 2026, U.S. Customs and Border Protection (USCBP) temporarily stopped operations at Montréal-Trudeau International Airport in Montreal, Canada, due to a strong odour detected in the customs area. This interruption led to the cancellation of approximately 20 flights bound for the United States.
Flight Cancellations and Passenger Delays
The suspension forced the cancellation of around 20 U.S.-bound flights, causing significant delays for international travellers. Passengers faced disruptions when processing through U.S. Customs, and additional flight delays and cancellations were possible as operations restarted gradually.
Cause of Suspension and Safety Assessments
The pause in U.S. Customs operations was triggered by a strong odour linked to varnish used in painting work
on construction materials located near the customs area. The Montreal Fire Department inspected the affected zone and confirmed that the odour did not present any health risks. Ventilation was increased to mitigate the odour presence while the area was evaluated.
Airport Response and Passenger Advisories
Montreal-Trudeau Airport authorities stated that every effort was underway to restore full U.S. Customs operations promptly. They advised passengers to verify flight status with their airline before traveling due to ongoing delays. Officials reaffirmed that the varnish odour was unpleasant but posed no health hazard and expressed appreciation for travellers’ patience during the disruption.
For inquiries regarding U.S. preclearance procedures,
passengers were directed to contact USCBP directly.
Infrastructure Redevelopment Background
The disruption occurred amid Montréal-Trudeau Airport’s extensive $10-billion redevelopment project, one of the largest infrastructure transformations in its history. Major construction is scheduled to continue throughout the next decade, contributing to the presence of construction materials near passenger processing areas.
