Best Buy shares skid on Thursday after the retailer said total revenue and sales at its established U.S stores fell in the all-important holiday season due to intense discounting by rivals, supply constraints for key products and weak traffic in December.
Sales at its stores open at least 14 months were down 0.9 percent in the United States and up 0.1 percent internationally in the nine weeks ended Jan. 4.
Total revenue fell about 2.6 percent to $11.45 billion in the nine-week period.
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"It's been a very challenging retail reporting season for retailers in general. I think that Best Buy got caught up in that. This also just shows the ongoing challenges in the consumer electronics business through the holiday selling season," Oppenheimer retail analyst Brian Nagel told CNBC's "Squawk Box" Thursday.
The world's largest consumer electronics chain cut prices aggressively to thwart fierce competition from Wal-Mart Stores and other rivals in what turned to be one of the most promotional seasons since the recession.
Best Buy's share price plunged more than 30 percent in premarket trading. (Click here for the latest quote.) Over the last 12 months, the stock had risen 161 percent, as investors warmed to the retailer's turnaround story.
"The promotional intensity that began with Black Friday continued throughout the period," said Chief Executive Officer Hubert Joly, who now expects the additional discounts to lead to a drop in margins.
The decision to discount aggressively, however, boosted Best Buy's market share at a time when overall industry sales fell, Joly said, citing data from research firm NPD Group.
Sales at stores open at least 14 months were down 0.9 percent in the United States and up 0.1 percent internationally in the nine weeks ended January 4. Total revenue fell about 2.6 percent to $11.45 billion in the nine-week period.
Best Buy expects the fourth-quarter operating margin, excluding items, to be 175 to 185 basis points lower than the year-ago period.
—By Reuters. CNBC contributed to this report.