Statistics Canada says wholesale sales fell 1.2 per cent to $64.3-billion in August.
Economists had expected growth of 0.3 per cent for the month, according to financial markets data firm Refinitiv.
Statistics Canada says five of seven subsectors, representing 85 per cent of wholesale sales, fell in the month.
The machinery, equipment and supplies subsector dropped for the second consecutive month as it fell 2.6 per cent in the month, while the personal and household goods subsector lost 3.4 per cent.
The motor vehicle and motor-vehicle parts and accessories group fell 1.2 per cent, the miscellaneous subsector lost 0.7 per cent and the food, beverage and tobacco subsector dropped 0.4 per cent.
Wholesale sales in volume terms decreased 1.3 per cent in August.
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