Online shopping is set to become the number one choice for shoppers in the U.S. this holiday season for the first time, a survey by accountancy firm Deloitte has found.
Deloitte interviewed over 5,000 U.S.-based consumers in September and found that 47 percent of consumers said the Internet would be their favorite shopping destination, while last year's favorite—discount department stores—slipped 7 percentage points to second place.
This is the first year that the Deloitte Annual Holiday Survey has identified the Internet as the preferred shopping method over traditional shopping in physical stores, which 37 percent said they still preferred.
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"Online shopping overtook traditional retailing for the first time in the survey's 15 years as consumers seek lower prices available over the Internet and the convenience of shopping anytime, anywhere," said Deloitte.
Deloitte also found that this year there was a strong link between the acceleration of online shopping and rising smartphone use.
Nearly seven out of ten of smartphone owners will use their smartphone for holiday shopping, Deloitte found, with 'finding store locations' and 'checking and comparing prices' being the top two uses. While 45 percent of consumers said they will use social media to assist with their holiday shopping.
A total of 61 percent of surveyed consumers now own a smartphone, a 19 percentage point rise from last year, and the strongest pick-ups have been seen for women, those aged between 18 and 34 years, and for those who earn less than $100,000 a year.
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"Tablets are a two-way street for retailers," said Alison Paul, vice chairman, Deloitte, and retail & distribution sector leader.
"They have opened up an entirely new consumer touch point, where shoppers can view multiple retailers' products regardless of their location—from their couch to the point of purchase. Retailers can also put tablets to work in their stores, providing both their sales team and customers with a broader lens into merchandise selection."
Furthermore, according to a Euromonitor report on "Consumers in the Americas," which focused on North and South America shopping behavior over the holiday season, 84 percent of shoppers are now using smartphones as a "shopping companion" and one in three use their phone to address queries rather than asking an employee.
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Meanwhile, Deloitte found that six out of ten smartphone users thought they were better connected to consumer information than store associates.
Euromonitor International said the rising use of smartphones was most prominent in Latin America, where 75 million smartphones will be sold this year, compared with 52.2 million in 2012 and 35.5 million in 2011.
Another key trend this holiday season is the increasing demand for sourcing Christmas gifts from other cities or overseas, particularly in South America, the Euromonitor report found.
Shopping services which facilitate buying gifts from other countries and cities are multiplying. In Ecuador, for example, the national postal service launched its so-called Mail Club, through which consumers can shop online in Miami, the number of packages sent has increased by over tenfold in the past three years.
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Interestingly, South American shoppers are also increasingly looking to buy online from China. Digital research firm ComScore reported that visits from Argentines to Chinese shopping portals, like AliExpress, DealXtreme, FocalPrice and PandaWill expanded tenfold in the past two years.
Nearly every country in the Americas sees its heaviest consumption over the "holiday season" as it is known in the U.S. and Canada, and some retailers see 20 to 40 percent of their annual sales over this period, National Retail Federation data cited in the Euromonitor report showed.
—By CNBC's Katie Holliday. Follow her on Twitter @hollidaykatie.