US retail sales fell 0.3% in August, according to the Commerce Department.
Economists had forecast that sales fell 0.1% month-on-month, according to Bloomberg.
Consumer spending was a key driver of economic growth in the second quarter, and the data suggest that this may have briefly faltered in the third.
The declines were broad based, with retail stores at fixed locations, home improvement retailers, and carmakers recording some of the biggest month-over-month drops.
Excluding auto and gas sales, which can be volatile on a monthly basis, so-called core retail sales fell 0.1% (0.3% expected).
Weak auto sales in August were expected to be a drag. Ford, one of the so-called Big Three carmakers, said last month that for the rest of the year, it would be tough to match the pace of sales witnessed in 2015.
The retail sales control group, which excludes volatile items like cars, gas, food, and building materials and feeds directly into the government’s calculation of gross domestic product, fell 0.1% (0.4% forecast).