THOUSANDS of people who are paying extra for super-fast broadband have been warned there may be no point as they could be kicked off their package after just 20 minutes of usage.

Virgin Media’s top-end package costs £37 a month and advertises “unlimited” downloads, but customers could have their download speeds restricted if they breach a “fair usage limit” and a typical user could exceed this in less than half an hour, according to Broadband Choices, a comparison firm.

And the problem is set to get worse as the government urges the industry to increase broadband speeds. Last week, Stephen Timms, the competitive-ness minister, said Britain’s infrastructure lagged behind those of other global players. Almost nine out of 10 British internet users connect via broadband yet have to put up with some of the slowest speeds – we are five times slower than the French and 22 times slower than Japan.

The Virgin Media package is one of the fastest mainstream services in Britain. It allows for a theoretical 20 megabits per second (Mbps) download speed, but customers who use more than 3 gigabytes (GB) – about three good quality films or six episodes of Top Gear – during the peak hours of 4pm to midnight, have their speed reduced to 5 Mbps for the next four hours – a quarter of the paid-for speed.

Broadband Choices said Virgin customers could exceed their limit in 20 minutes at the top advertised speed. “It defeats the purpose,” said the firm’s Michael Phillips. “These products urge people to download more often as they highlight top speeds.”

He said internet service providers should offer preferential treatment to customers on high-end deals. “If you’re paying a premium, then you shouldn’t have the same restrictions as other customers who are paying less.”

Virgin Media said reaching the limit within 20 minutes was “a fact of the current set-up”. It added that internet “traffic management” was a way of making sure the majority of customers received a decent service.

Broadband providers have a limited bandwidth which they have to share between their customers. If one customer hogs it, others suffer.

Virgin said only 5% of its customers are affected by the restrictions although this accounts for about 165,000 households.

Other providers that are open about how much they will allow you to download before imposing restrictions are Demon, Toucan, Madasafish, AOL, PlusNet and Pipex although they do not offer speeds above 8Mbps.

Sky offers an up to 16Mbps service for £25, though this also includes a basic Sky TV package. Again, the advertising says it allows for unlimited downloads, subject to a fair-usage policy, but unlike Virgin does not offer customers a clear indication of what these limits are.

The Sky broadband small print reads: “To impose an actual figure on what we consider to be ‘excessive’ use is not necessarily helpful.”

Also, unlike Virgin, if you continually exceed your limit and are deemed to have breached the fair-usage policy, your service could be suspended altogether.

Other providers offering super-fast broadband include Be and O2 though neither provides clear details of fair-usage limits.

Speed is one of the most important factors when deciding which broadband to go for. Comparison firm Uswitch said 58% of customers prioritise speed over value for money. However, its research also said 25% of broadband users did not know what speed they had signed up to and 31% didn’t know what speed they actually received.

Ofcom, the regulator, said 58% of customers paying for an “up to” 8Mbps service actually received lower speeds, while 40% of connections were only capable of receiving 2Mbps.

Ofcom has written to the top six providers asking them to provide consumers with clearer information on what speed they are getting, as opposed to the maximum advertised speed.

Noncable companies such as BT and Sky are limited in the speeds they can provide through the “copper wire” infrastructure that supplies broadband to homes. The further the customer lives from a BT exchange, the weaker the signal and the slower the speed.

Some providers, such as 02, give you the option of downgrading your package if the speed you sign up for is unachievable. Before you are hooked up to its network, the firm will offer an online test to find out which is the best product for you.

O2 offers a 20Mbps service, but charges £25 a month – £12 less than Virgin. If you are an O2 mobile customer, the rate is £15 a month. If a customer later discovers that they are still not getting the speeds they're paying for, O2 will allow them to down-grade without any extra cost.

Use the speed-test tool on broadbandchoices.co.uk. Use the tool at different times of the week to get a better overall picture. The website also offers a download monitor that can tell you when you are getting close to your download limit.

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