E-commerce in the UK generates over £100bn for the economy, or 7.2 per cent of the nation's gross domestic product (GDP), according to a report by the Boston Consulting Group.
Britons spend a higher proportion of their money online than any other Organisation for Economic Co-operation and Development nation, and the reports suggests that the UK digital economy will grow to 10 per cent of GDP by 2015.
"The internet is more pervasive in the UK economy today than in most advanced countries," said Paul Zwillenberg, a partner at Boston Consulting Group.
"Whether they are driving international expansion, improving their interactions with customers or the efficiency of their supply chains, UK companies are increasingly embracing the internet's potential.
"Several industries, including media, travel, insurance and fashion, are being transformed by it."
The UK internet sector employs around 250,000 people, the report found, and has a positive balance of electronic trade, exporting £2.80 for every £1 imported.
The average person spent 24 hours online in April, and mobile internet access is used by 31 per cent of Britons, rising to 44 per cent among the 16-24 age group.
"We all know how the internet has changed the way people access information and communicate," said Matt Brittin, managing director at Google UK, which sponsored the research.
"Now for the first time we can see how its adoption by British business has become a major contributor to the UK's GDP, and that the internet is a central pillar of the UK's economy.
"The sector has come of age and, with great prospects for further growth, will be vital to the UK's future prosperity."
London is the leading e-commerce region in the country, followed by the South East and the East of England. Wales, Scotland and Northern Ireland are the least important e-commerce regions in financial terms.
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