Twenty-three GP practices in Northern Ireland continue to use 0844 telephone numbers which can charge people up to £8 to book an appointment, the chairwoman of the health committee said on 20 May 2012.
Sue Ramsey of Sinn Fein explained that 0844 numbers were "not linked to a particular town or country" and organisations using them were permitted to receive a share of the call charge revenue.
Ms Ramsey said Health Minister Edwin Poots had previously said that these numbers would not incur the extra charge if used from a landline, however, she claimed the most vulnerable in society would continue to be the worst affected as many were reliant upon pay-as-you-go mobiles.
"The least able to pay in our society end up paying the most to access a basic health service", she added.
Her party colleague Mickey Brady highlighted a case were a patient had spent £17 booking an appointment from a mobile.
The deputy chairman of the committee, Jim Wells of the DUP, said the cost to an 0844 number from a landline ranged from 2-4 pence a minute, but that this rose to between 25-40 pence on pay-as-you go mobiles.
Ulster Unionist Ross Hussey said: "The time has come to do away with 0844 numbers - the cost is excessive, they don't work and older people will not remember the numbers."
The SDLP's Mark Durkan said "healthcare should be free at the point of use" but was not a "not a widespread problem" as it was only used in 23 out of 355 practices.
Kieran McCarthy of the Alliance Party said had had been "shocked" to learn that three of the practices were within his own constituency of Ards.
In response, the health minister said measures had already been taken to stop the use of extra charges although his department had no legal power to put a ban in place.
"Practices must consider introducing a system under which, if a caller asks to be called back, they will do so at their own expense and they will not enter into new, renew or extend contracts for telephone services unless they are satisfied that patients will not pay more than they would to call a local geographical number," he said.
Mr Poots said the process of stopping the use of 0844 numbers would have to be flexible to accommodate practices and the contracts they had entered into.
He said 17 of the 23 practices had said that they would not renew their 0844 contract.
The minister said three of these would expire in 2013, four in 2014, six in 2015 and four in 2016.