Shares of Guess Inc. soared as much as 21 percent after the L.A.-based apparel company reported Thursday that its September same-store sales surged 14.2 percent, beating analysts’ estimates of a 3.2 percent increase.

Total retail sales for September jumped 25.3 percent to $57.6 million from $45.9 million a year earlier. Guess said sales for the month were driven by a larger percentage of full-price non-discounted sales compared to the prior year.

For the third quarter ended Oct. 1, sales in stores open at least a year edged up 8.9 percent, while total retail sales rose 19.6 percent to $156.3 million, compared with $130.6 million in the prior-year period.

As of Oct. 1, the company owned and operated 305 retail stores in the U.S. and Canada. Guess also distributes its products through department and specialty stores.

Shares of Guess rose 17.7 percent to settle at $24.43 on Thursday.