The companies – Vertical Media Ltd, Fast Way Holdings Ltd, Litmus Ltd, Indiano Communications, Greenbay Ltd and Quartel Ltd – are all based overseas but use the same UK agent, a Bury-based company known as Smile Telecom.
According to the Independent Commission for the Supervision of Standards of Telephone Information Services (ICSTIS), all six companies were involved in sending unsolicited text messages, making unsolicited phone calls and using automated calling equipment to leave 'missed calls' on mobile phones.
These actions, said ICSTIS, were deliberately designed to trick people into calling premium rate numbers (at up to £1.50 per minute) to claim prizes that either didn't exist or, at best, were woefully below what was promised.
Each has been fined £75,000 for breaching the ICSTIS Code of Practice and has been barred from operating premium rate services in the UK.
According to ICSTIS Director George Kidd: "The case is of particular concern as the six companies all have the same UK agent operating on their behalf."
"We have instructed redress to be paid to those affected but Smile Telecom has refused to compensate complainants unless requested to do so by its six clients," he added.
The DTI, Ofcom and the police have been informed, and investigations are continuing, says ICSTIS.
Communications Minister Stephen Timms said:
"Consumers who get ripped off by these scams will be pleased to see that justice has been done. These get rich quick schemes damage the reputations of legitimate operators. We are determined to work with ICSTIS and other groups to weed out these fraudsters and make sure that such scams are confined to the past."