A card sits on your doormat, cheerily claiming that Company X tried to deliver you a prize. “Please phone us to arrange delivery,” it glibly asks. Unbeknown to you, this means a premium-rate call that could well cost £10, and almost certainly won’t furnish you with that promised DAB radio.

The consumer watchdog Which? reports that more than one in three adults in the UK has received such offers, of whom 2m have, amazingly, taken the bait, lured by free holidays, cash or new cars, and wasted money by listening to messages at £1.50 per minute. This is now the most widespread racket in the country.

Premium-rate services are worth £1.5 billion per year, according to Icstis, the industry-funded regulator. With so much at stake, neither Icstis nor Ofcom, to which it reports, seems able to stop the hucksters. Icstis also says that people overestimate its powers: “If there’s a scam, then it’s up to the police to investigate, and they often have more important things to do.” Icstis tries to defer to Ofcom, saying that it is responsible only for content and promotion, not phone networks.

“The relationships between customers, the middlemen and various telcos are very complicated,” Ofcom said. “Where a rogue provider sets out to scam consumers, it’s difficult to identify that within the overall revenue stream.”

With so much buck-passing, it’s no wonder that consumers are being fleeced. At least Icstis’s new fines of up to £250,000 for “spam and scam” tactics mean that when rogues are caught, they pay a whopping price.

Yet rip-offs are merely one symptom of a telephone numbering system that is plainly out of control and confusing to all but the super-numerate. Most people know that it costs nothing to call, say, Amazon on an 0800 number, to check up on your order of Alan Sugar’s The Apprentice. Yet how are we to know that calling Lastminute’s 0871 number to book a fancy weekend in Brooklyn costs 10p per minute? Or that a glimpse into the future from Live Psychic Readings’ 0906 hotline costs £1.50 per minute? They must have seen us coming.

Thank heavens, then, that public vexation has persuaded Ofcom to propose simpler, tariff-related dialling codes and enable consumers to bar premium-rate scams, too. For a start, both 08 and 09 prefixes would, in future, be followed by a digit that reflects price. Calling 082, for example, would be cheaper than 089.

As well as indicating cost, these new numbers would, in theory, enable parents to bar children from calling premium-rate sex-talk lines. Even better, if you hate companies that use high-priced 0870/1 numbers to increase profit while providing basic customer services, Ofcom is proposing a new 03 nationwide prefix, charged at the same rate as geographic numbers such as 0161 (for Manchester).

Whether companies will use the new numbers and forgo revenue is debatable. If they were serious about customer service, they would have adopted the free 0800 numbers.

Simplifying the current brain-taxing system sounds sensible, but initial reactions were mixed from Craig Skinner, a numbering expert at the telecoms researcher Ovum. “Most concern centres on the 08 and 09 number ranges, where the changes will be difficult to manage. This will require education of customers and significant cost for individual business.”

What of the scammers? Ofcom plans to change the way numbers are allocated, and threatens to deny numbers to phone networks that have hosted service providers which have abused consumer trust. So, if fraudsters use their networks illegally, the responsibility for policing the premium-rate market passes to the private sector. Skinner said: “The ban on revenue-sharing on 03 numbers might help, but this won’t clear up scams among companies that choose to stick with 08 and 09 numbers.”

Ofcom has a table illustrating its proposals at tinyurl.com/ezgww, and the consultation runs until May. Doors invites your suggestions for improving telephone numbering, which we will forward to the regulator. Mail them to doorscampaign@sunday-times.co.uk.

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