The move is part of an Ofcom review of "non-geographic" numbers
The cost of calls to 0870 numbers will be cut under proposals by the regulator after complaints about price clarity.
The number is typically used by consumers when calling customer services departments or seeking advice such as traffic information.
Regulator Ofcom wants prices to come down from a typical daytime tariff of 6p to 10p per minute to 3p to 4p.
More expensive 0871 numbers would also be regulated by the premium-rate watchdog, under Ofcom's proposals.
The plans, which Ofcom wants in place by the autumn, are part of a wider review of so-called "non-geographic" numbers - which are not assigned by location.
The 0870 numbers are used by a wide range of businesses and organisations offering anything from traffic information to financial services.
Consumers have complained to Ofcom about a lack of transparency in pricing.
On average these calls cost between 6p and 10p per minute in the daytime from a BT landline and 1p to 5p at other times.
Ofcom wants this to be reduced to around 3.5p a minute in the day and 1p to 1.5p a minute at other times - similar to "geographic" telephone numbers.
The proposals would effectively rule out companies or organisations sharing the revenue generated by the calls.
Those which wanted to charge more would have to abide by strict rules on how call charges were advertised.
"The continued high prices of calling 0870 numbers, particularly from mobile phones, remains a shame and a scandal," said Ofcom Consumer Panel chairwoman Anna Bradley, who welcomed the proposals.
The plans now go to a consultation process
"It is simply unacceptable that consumers are paying up to 25p a minute to call 0870 numbers from mobile phones, or 10p a minute from a landline, when compared to the lower costs of calling geographic numbers."
In a separate decision, Ofcom announced plans to improve consumer protection for calls to more expensive 0871 numbers.
It wants these numbers to come under the remit of PhonepayPlus, the premium-rate regulator.
Under the watchdog's rules, prices would have to be published on any advert or promotional material for an 0871 number and excessively long call queuing times could also be investigated.