U.S. Customs and Border Protection (USCBP) temporarily suspended operations at Montréal-Trudeau International Airport on Wednesday, July 29, 2026, due to a strong odour originating near the customs area. This suspension led to the cancellation of approximately 20 flights to the United States.
Cause and Extent of Flight Disruptions
The odour was linked to varnish fumes from painting work associated with nearby construction materials. The Montreal Fire Department inspected the affected area and confirmed that the odour posed no health hazard. In response, ventilation was increased to mitigate the issue. Despite these measures, the presence of the odour forced the halt in USCBP operations, directly impacting passenger
processing and flight schedules for U.S.-bound departures.
Official Responses and Travel Advisory
Airport officials indicated that USCBP operations were gradually resuming at the time of reporting but warned that delays might continue. The Montréal-Trudeau Airport’s official website advised passengers to verify their flight status with airlines before traveling to the airport. Officials emphasized ongoing efforts to restore full customs services as swiftly as possible and apologized for the inconvenience caused.
Context of Ongoing Redevelopment
The incident took place amid a $10-billion redevelopment project at Montréal-Trudeau International Airport. The infrastructure transformation, expected to span the next decade, involves extensive construction work around the airport, including the area near U.S. customs
preclearance facilities. This ongoing construction has been identified as the source of the varnish odour triggering the customs suspension and associated flight cancellations.
