THE cost of calling 0870 numbers will be slashed to the same price as national landline rates, the telecoms regulator said.
Businesses will no longer get a cut of revenue generated by calls starting with this code, according to Ofcom.
The changes follow customer concerns over unclear pricing and marketing of "non-geographic" numbers such as those starting with 0870.
Companies which continue to charge extra must warn customers about their prices free of charge at the start of the call.
Daytime calls to 0870 numbers from UK landlines typically cost about 8p per minute compared to 3p per minute for a call to a 01 or 02 landline.
The changes will affect calls made from both landlines and mobile phones.
An Ofcom spokesman said: "Consumers have had some specific concerns about 0870 numbers.
"What we have confirmed today are changes which bring the cost down and will end the opportunity for revenue sharing on these numbers. Organisations won't have the opportunity to make money out of call charges on 0870."
Adult services must move from 08 numbers to the designated 09 range, the regulator said today.
All such services - plus numbers in the 0871 range - will come under the remit of premium rate regulator ICSTIS.
Companies using 0845, 0844 and other 08 code numbers must provide customers with more accurate price information. The cost of calling these numbers will not change, the regulator said.
Ofcom will review 0845 call rates - used by some five million UK dial-up internet users - within two years.