Online US holiday sales seen growing 17 percent

The report from the research firm comScore showed retail e-commerce spending for the first 18 days of November-December holiday season were up 16 percent to $10.1 billion.

November 8 has been the heaviest online spending day of the season to date at $829 million, comScore said.

"The 2012 online holiday shopping season is off to an encouraging start with a 16 percent growth thus far," said comScore chairman Gian Fulgoni.

"Recent five-year highs in consumer confidence and early retailer promotions appear to be serving as wind in the sails for the beginning portion of the holiday season, with consumers opening up their wallets early and often."

The comScore forecast of a 17 percent gain would outpace last season's 15 percent increase and would be well ahead of the retail industry's expectation for a 4.1 percent increase in consumers' overall spending this holiday season.

"The strength leading up to and during the holiday season-to-date, in addition to a maximum 32 shopping days between Thanksgiving and Christmas, provide the basis for what we view as a fairly optimistic outlook for the 2012 online holiday shopping season," said Fulgoni.

US government data showed ecommerce sales for the third quarter from August-September rose 3.7 percent to $57 billion, and accounted for some 5.2 percent of all retail sales.