Statistics Canada says wholesale sales fell 0.6 per cent in July to $80.2 billion, led by a drop in the personal and household goods subsector.
The agency says sales fell in five of seven subsectors, which represented 63 per cent of wholesale sales.
Sales of personal and household goods fell 2.6 per cent in July to $10.8 billion as the textile, clothing and footwear industry fell 13.2 per cent.
The building material and supplies subsector saw sales fall 1.7 per cent to $12.8 billion for the month as sales of lumber, millwork, hardware and other building supplies lost 2.8 per cent.
Meanwhile, sales of machinery, equipment and supplies rose 1.6 per cent to $17.0 billion.
Overall, sales in constant dollar terms fell 1.0 per cent in July.