Millions of families are missing out on savings running into billions of pounds because they do not use the internet, the Government's digital inclusion champion said today.
Some 10 million people - 17 per cent of the entire population - have never been online, and four million of them come from economically or socially excluded backgrounds, according to research carried out for internet tsar Martha Lane Fox.
She warned today that those without access to the web were missing out not only on shopping bargains, but also work and training opportunities and official information on issues like the swine flu outbreak.
Ms Lane Fox was appointed by Prime Minister Gordon Brown in June this year to represent people not yet online and create a plan to bring the web to the socially disadvantaged.
The first piece of research produced for her by PricewaterhouseCoopers found that the average family would miss out on savings totalling £560 a year if they did not use the internet to shop around for the cheapest deals on products like energy, insurance and household items. The four million economically and socially excluded people without internet access were missing out on an average £300 annually - a total of £1.2 billion.
The report also found that 1.8 million children growing up in digitally excluded families could increase earnings by more than £8,000 each over their lifetimes - a total of £10.8 billion - by becoming web-literate.
Ms Lane Fox, best known for founding shopping website lastminute.com, said that the four million economically and socially excluded individuals who were not using the net included 39 per cent who were aged over 65, 38 per cent were unemployed people living without children and 19 per cent were families with children.
She told BBC Radio 4's Today programme: "As a consumer, you are missing out on great savings if you don't shop online, let alone the fact that more and more Government services are going to become digitised.
"If you look at the recent swine flu scare, think about how much information was online and how much more quickly and timely you got the information.
"I think it is worth fighting for the rights of people to have the same choices and access to the same benefits as all of us who are web-enabled."