Costco Wholesale Corp. shares rose more than 3% Thursday after the company posted surprisingly strong sales numbers for November, drawing applause from analysts.

The biggest warehouse club in the U.S. “turned in a month for the ages in the current retail environment,” said Ken Perkins, analyst at data firm Retail Metrics.

Costco COST, +1.43% said same-store sales rose 10.8% in November, its biggest monthly gain in more than six years going back to September 2011, when it posted a 12% gains, said Perkins.

Net sales climbed 13% to $11.26 billion from $9.95 billion in the same period a year ago. E-commerce sales alone rose 39% in the month, and were up 44% in the 12-week period through Nov. 26.

Growth was spread across most categories, with hard-line comparables up in the low teens, midteens gains in appliances, tablets and computers, and strength in auto, tires, sporting goods and office.

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Softlines gained in the high single digits led by jewelry, clothing and home products. Food and sundries rose in the mid-to-high single digits, led by cooler, candy & tobacco. In the fresh food category, bakery, deli and meat were strong performers.

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Susquehanna analyst Bill Dreher raised his 2018 estimates on the news and said it looks as if margins held up even in the face of hurricanes and higher gasoline prices.

“Admittedly, gross margin can be a bit of a wild card for Costco, depending on how management is investing in the long-term health and competitive positioning of the business,” he wrote in a note. “Our model only looks for a 1 bp expansion in gross margin for the first quarter of fiscal 2018, on top of the +29 bp last year, so we pretty feel good about our seemingly conservative estimate.”

UBS analysts led by Michael Lasser said the company has now reported six straight months of more than 4% growth in traffic in the U.S., its largest market, even after it raised membership fees on June 1.

That shows “that there’s still room for bricks and mortar retailers to succeed in today’s environment, provided they have the right differentiated model,’ he wrote.

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“In Costco’s case, mid to high single digit core same-store sales growth should help it increase its buying power, which it can then use to pass along savings to its member base. This should keep Costco’s virtuous circle spinning, and support its shares.”

10 'unexpected' bargains at Costco

In other positive news for Costco, a recent survey by LendEDU found that the average price increase when shopping for 38 identical items on Amazon.com Inc. AMZN, +5.69% versus Costco is about 56%. The online marketplace for student loan refinancing found that the total price increase when shopping on Amazon instead of Costco is 12%.

Costco shares have gained 14% in 2017, while the S&P 500 SPX, +1.05% has gained 17% and the Dow Jones Industrial Average DJIA, +0.51% has gained 22%.

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