The firm said hiring for October, November and December reached 728,300 in 2012, up 10.3 percent from the same months of 2011, when 660,200 seasonal jobs were added.
Retail hiring for the end of 2012 was at the highest level since 2006, when 749,900 jobs were added to the economy.
Chief Executive Officer John Challenger said the hiring for 2012 was "remarkable for a few reasons."
Challenger cited the gain in e-commerce, where businesses typically do not hire as many extra employees during the holidays as brick and mortar stores, and "stubbornly low" wages through the economic recovery, which meant that consumers did not have much to spend this year relative to other years.
But 2012 included an early Thanksgiving, which may have accounted for the extra hiring, given the day after Thanksgiving, "Black Friday," signifies the start of the holiday shopping season.
The early Thanksgiving may also help explain why hiring for December 2012 tailed off sharply compared to November.
Retailers added 149,600 jobs in October 2012. In November, 490,400 jobs were added. And in December hiring dropped to 83,300, the firm said.
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