US sales from internet retailers rose 19% between 1 November and 27 December compared with the same period of 2006, a report estimated.
The online information group comScore said that online spending excluding travel and auctions came in at almost $28bn (Â£14bn).
It said that the growth is impressive given the current economic problems.
But the 19% growth was well below last years rate of 26%, which the firm blamed on warm weather in November.
"Warm weather during the early part of November took its toll on online retail sales, and played a role in holding down the growth in spending over the entire holiday season," said comScore chairman Gian Fulgoni.
View: BBC News