The BBC’s free iPlayer and similar services could end up costing consumers more than the price of a video box set, Broadband Choices has warned.

Those with fixed monthly download rates could unknowingly be going over them when using iPlayer and be charged extra by their ISP, the price comparison website has said.

The iPlayer, which uses legal file sharing downloading software, downloads around 400 hours of BBC programming per week. This can then be watched at any time by the viewer for the next 30 days.

However, according to Broadband Choices, the iPlayer cannot be turned off meaning it is left in the background to continue to download content “regardless of a user’s download limits.”

Michael Philips, product director at Broadband Choices, told Computeractive: “It’s all very well the BBC offering customers a free download service but those with a maximum download package set by their ISP could end up paying a fortune.”

He used the example of Madasafish, which charges customers £2 per GB, or part thereof, with a maximum charge of £99.99 a month.

Tiscali also warned this week that services such as the iPlayer could push up the price of broadband as the amount being downloaded could cause traffic jams and may mean that networks need urgent upgrades to cope with them.

The telecoms regulator Ofcom estimates that such upgrades would cost at least £830m, a cost Tiscali warned would be pushed onto consumer who would begin to see higher monthly charges.

Mary Turner, chief executive at Tiscali, said: “Our position is that high bandwidth content services like iPlayer are being launched without proper attention to the cost of delivery."

Both companies have now called for the BBC to review the way it runs its service. Until then, Mr Philips advised those wishing to use the iPlayer or similar services are advised to sign up to a broadband package with unlimited downloads.

A BBC spokesman said the network was discussing with ISPs on how best to tackle the situation.