As the holiday spending season kicks off, online shopping is emerging as a clear winner, helped by increased use of mobile phones.

E-commerce accounted for 25% of consumer spending on Black Friday and the two days prior, up from 18% last year and nearly double the figure for the same period four years ago, according to First Data Corp., which analyzed point-of-sale data at nearly one million merchants.

Online shopping is more popular during the holiday shopping season, which starts around Thanksgiving. By contrast, e-commerce sales in the third quarter accounted for just 8.4% of total retail sales, according to data from the U.S. Commerce Department

During the three days through Black Friday, total retail spending, including at brick-and-mortar stores, grew 9% from a year earlier, slightly less than last year because more stores opted to remain closed on Thanksgiving, First Data said. As a result, overall spending dipped early Thursday, but picked up around 6 p.m. that day, when many large chains opened their doors.

Much of the online traffic was driven by mobile phones. Adobe Systems Inc., which analyzed 23 billion website visits, said mobile phones accounted for 36% of Black Friday's online sales this year, up from 26% in 2014. Wal-Mart Stores Inc. said 60% of its online orders on Friday came through mobile devices, up from 50% last year.

The pace of online spending continued into Cyber Monday, when e-commerce sales rose 12% from a year earlier to $3.45 billion, according to Adobe.

The surging levels of web orders will test retailers' fulfillment and logistics operations and put added pressure on shipping companies like United Parcel Service Inc. and FedEx Corp., which will have to deliver millions of packages to consumers' homes in the weeks leading up to the year-end holidays.

Sales got off to a strong start in the week leading up to Black Friday, when they grew 5.3% from a year earlier, according to First Data. Much of the growth occurred on the Wednesday before Thanksgiving, as consumers started their shopping earlier.

RetailMeNot, which analyzed proprietary data that tracks discounts, found that 70% of retailers started promoting Black Friday offers before Thanksgiving, and that the average duration of the offers was 10 days.

Electronics and appliances were the best-performing category on Thanksgiving and Black Friday, with sales up nearly 27% from a year earlier, First Data found. Clothing and accessories grew 10%, as did sporting goods, while health and personal care was up nearly 8%.

Sales in the Eastern U.S. were helped by a cold snap, while sales in states west of the Mississippi were hurt by warmer than usual temperatures, according to Planalytics, which analyzes historical weather patterns and industry sales data. For instance, sales of women's boots were up 12% in Hartford, Conn., but down 19% in Denver, Planalytics found.

(END) Dow Jones Newswires

November 29, 2016 15:55 ET (20:55 GMT)

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