Numbers starting 090, 091 and 098 are designed to be used for chargeable services paid for as the call is being made. Rather than spend the first few minutes of the call taking your bank details to pay for the service, the charge is instead levied as an additional Service Charge paid through the caller's telephone bill. Services using this payment mechanism include voting on a TV show, recorded information lines, chatlines, adult entertainment, etc. Numbers starting 09 are among those that are banned for customer services, financial services, public services and healthcare services.

The same charging mechanism also applies to 084 and 087 numbers, albeit with much lower Service Charges. Where these numbers have been inappropriately used for customer services, sayNOto0870 has publicised alternative geographic numbers. However, things have moved on. Various regulations have since forced most of those companies to change their numbers. Nowadays, sayNOto0870 exists mainly to publicise alternative numbers for those who have failed to comply with the regulations.

I see very little evidence of customer service lines using 09 numbers so I am not sure what issue you are trying to solve. The vast majority of 09 numbers are genuine chargeable services relying on the Service Charge revenue to fund the service, and hence there is no alternative number available to be publicised here. People have the choice of wasting their money voting on a TV show contestant or not. The issue of organisations using expensive telephone numbers for inappropriate purposes existed mainly on 084 and 087 numbers and has been largely solved.

Very much agree with Ian01. Most of the 084/087 offenders have gone though there are still quite a few around. 09 numbers are genuine premium rate and recognised as such by most people.

That just leaves a few anomalies that need to be dealt with. 070, which isn't for mobiles and much more expensive to phone. Now mostly used for scamming AFAIK. Other oddities include 0500 (freephone but charged from mobiles) which is more or less gone and other 05 series numbers where I've not got the foggiest idea how they are charged. Again quite rare now. There are just a few 01x geo numbers and 07x mobile numbers used by Isle of Man and Channel Isles that look like normal numbers and charged at higher rates. I think that's it unless you know otherwise.

Phonepayplus already have the power to clamp down on abuse of 09 numbers. Perhaps they need some prodding.

Otherwise Ian01 is right, we've come a long way towards draining the swamp of UK phone numbers. There's still a rump of 084 and 087 numbers - they really need to be discontinued along with 070 and sooner rather than later. Then all revenue share services can go where they belong, to 09 numbers where almost everyone knows they will be charged a premium.

Premium rate numbers start 070, 084, 087, 090, 091, 098 and 118 plus various five-digit mobile shortcodes.

Call charges for calls to 084, 087, 090, 091, 098 and 118 numbers are split into Access and Service Charge components making these call charges transparent.

Call charges for any particular five-digit mobile shortcode are the same on every mobile network.

This leaves only the 070 and 076 ranges with non-transparent call charges and numbers that can be mistaken for mobile numbers.

Numbers starting 055 and 056 are not premium rate, but call charges are not well publicised.

The review of 055, 056, 070 and 076 numbers cannot come soon enough. However, by delaying the review while they sorted out the 084, 087, 09 and 118 ranges, Ofcom have made the issues with the 05 and 07 ranges even more obvious to see and left the door open for radical solutions to be proposed.

Of all on that list, 070 and 076 are up for review, perhaps next year and declining usage of 084 and 087 could see those being reviewed in a few years time. In the very long term, that would leave just 09, 118 and mobile shortcodes as numbers charged at a premium rate.

The "unbundled tariff" has brought clarity to call charges for 084, 087, 09 and 118 numbers, but not everyone has complied. Breaches can be reported to ASA. Looking at ASA Adjudications, they don't appear to have received any complaints on this matter.

Call charges for calls to five-digit mobile shortcodes must be declared alongside the number wherever it is advertised or promoted. While the charge varies from number to number, the call charge for any particular number is the same on every mobile network. There is no "standard rate".

However, when it comes to texting, there is a problem. Text messages sent to five-digit mobile shortcodes are either free-to-sender or are charged as "one standard rate message". These messages are non-inclusive but mobile providers have failed to explicitly state that fact or to list the cost of "sending one standard rate message to a five-digit mobile shortcode" in their tariff details.

Once you send the text message, there may be no reply, there may be a reply with no further charge or there may be one or more replies with a premium charge of up to £10 per message. Some services are subscription based, signing you into regular delivery of chargeable messages until such time as you send STOP to end the subscription.