Installing high speed broadband in every home in the UK could cost almost £30 billion, an industry report said.
The figure comes in a report by the Broadband Stakeholder Group (BSG) - the Government's advisory group on broadband - on the costs of fibre-based next generation broadband in the UK.
And it reveals a big difference in the cost of supplying superfast internet between built-up and rural areas. The report says supplying every home with next generation broadband could cost between £5.1bn and £28.8bn, depending on the technology used, and that the costs of deploying in rural areas will far exceed the costs in towns and cities.
Antony Walker, chief executive of the BSG, said: "This is the most comprehensive analysis produced to date on the costs of deploying fibre in the UK. The scale of the costs looks daunting but the report does shed light on how some of these costs can be reduced and what the likely extent of commercial rollout will be.
"It should focus minds of commercial players, policymakers and regulators on the potential solutions to these challenges."
The model demonstrates that national deployment of fibre to street-level boxes, the cheapest technology option, would cost £5.1bn. This is three or four times more than the telecoms sector spent deploying today's broadband services.
Taking fibre to every UK home using point-to-point fibre, the most expensive option, would cost as much as £28.8 bn. Superfast broadband will allow speeds of up to 100 Mbps (megabits per second), up to four times faster than current speeds.
A report by the government regulator Ofcom last week said communities that have missed out on broadband should be the first to get even faster services.