U.S. Customs and Border Protection temporarily suspended operations at Montréal-Trudeau International Airport on July 29, 2026, resulting in around 20 U.S.-bound flights being cancelled. This immediate halt affected customs processing for flights departing to the United States.
The suspension was triggered by a strong odour of varnish linked to painting work and construction materials near the U.S. customs facility. The Montreal Fire Department inspected the area and confirmed the odour posed no health risk despite its intensity.
Ventilation in the customs area was increased to address the varnish odour. U.S. Customs operations have been gradually resuming, though some delays remain
as services normalize. Airport officials stated efforts are ongoing to restore full operations as quickly as possible.
Passengers flying to the United States through Montréal-Trudeau International Airport are advised to verify flight status with their airlines before traveling due to ongoing delays and cancellations related to the temporary suspension of U.S. customs processing. They were also advised to contact U.S. Customs and Border Protection directly for questions about preclearance operations.
This incident occurred amid a $10-billion redevelopment project at Montréal-Trudeau International Airport, one of the largest infrastructure transformations in its history, with extensive construction continuing over the next decade.
