Strong online sales and demand for furniture and women's apparel helped U.S. retail sales grow by a "solid" 7.9 percent this holiday season, according to MasterCard Advisors SpendingPulse.

U.S. retail sales, excluding automobiles and gas, grew 5.5 percent in the period between Black Friday and Christmas Eve last year.

Online sales grew 20 percent in the holiday season this year, MasterCard Advisors, which tracks customer spending, said in a report on Monday.

"The double-digit growth in furniture sales ... shows that consumers are willing and able to splurge on big-ticket items," Sarah Quinlan, senior vice president of Market Insights at MasterCard Advisors, said in the report.

A delay in the onset of cold weather pushed back apparel buying this fall, so there was pent-up demand that played out after Black Friday, she said.

Quinlan said consumers were spending the money they were saving from lower gas prices.

The National Retail Federation, a leading industry group, has forecast a 3.7 percent rise in store and online sales in November and December this year, with online sales expected to rise 6-8 percent.