Costco’s popularity during the pandemic showed no signs of waning last month with shoppers flocking to both its warehouses and online store.

Over the five weeks ended 5 October, the group’s total sales rose a stronger-than-expected 16.9% to $16.84bn with comparable sales (excl. the impact of fuel and currency fluctuations) also up 16.9%.

Comparable sales rose 16.7% in its US business and climbed 18.0% in Canada. Sales in its international division rose 17.5%.

Meanwhile, e-commerce sales jumped 90.1% as Costco continued to benefit from the surge in online shopping during the crisis.

“September sales were positively impacted by two holiday shifts, Labor Day in the US and Chuseok/Moon Festival in Asia,” Costco said in a statement. “The estimated positive impact on September sales was slightly less than 100 basis points worldwide, half relating to each holiday.”

The September figures extend a trend Costco updated on last month when it posted bumper fourth-quarter earnings and sales figures.

Costco currently operates 796 warehouses, including 552 in the US and Puerto Rico, 102 in Canada, 39 in Mexico, 29 in the UK, 27 in Japan, 16 in Korea, 13 in Taiwan, 12 in Australia, three in Spain, and one each in Iceland, France, and China.