The Advertising Standards Authority (ASA) and Committee of Advertising Practice have asked Britain’s Internet service providers (ISPs) to overhaul the way they advertise broadband speeds, laying strict terms for those that advertise "unlimited speeds."

In new guidelines on what broadband providers can claim, their adverts can no longer claim that ‘up to’ speeds, but figures based on actual testing of the service.

The regulators have asked the ISPs to abide by the new standards by April 2012.

Now, any speed claim must be achievable by at least 10% users. The term superfast must be qualified with a number that can be achieved by 10 per cent and speeds must use ‘up to’ and include qualifications, according to the new guidelines.

The guidelines say, "’Unlimited’ are likely to be acceptable provided that: the legitimate user incurs no additional charge or suspension of service as a consequence of exceeding any usage threshold associated with an FUP, traffic management policy or the like, and provider-imposed limitations that affect the speed or usage of the service are moderate only and are clearly explained in the marketing communication."