It says travel to Canada decreased as a result of fewer trips from overseas countries.
The agency says Canadian residents took 4.7 million trips to the United States in September, up 0.5 per cent from August.
Same-day car trips to the U.S. rose 1.2 per cent, while overnight travel declined 0.5 per cent.
Travel to overseas countries continued to increase, as Canadian residents took 810,000 trips in September, up 0.7 per cent from August.
While travel from overseas countries fell 2.9 per cent, travel to Canada from the United States was unchanged at 1.7 million trips.