Patients who want to see a GP in the evening or weekend should face a charge, some family doctors say.
GPs will discuss the motion later this month
The charge would apply only to routine appointments and not emergencies, says the motion to be proposed at a British Medical Association GPs' conference.
Doctors said patients using surgeries at such times tended to be in employment and could afford to pay.
But patients branded the idea a scandal and the government said it would not be introducing payments for care.
The motion, put forward by a group of family doctors from across the country, states: "Resources for routine care outside core hours should be partially or wholly provided by a fee charged to the patient."
A fee of between £15 and £20 has been suggested.
It will be discussed by GPs later this month.
The idea comes amid widespread criticism for GPs over their high salaries.
About a third of their pay now comes from bonuses for meeting targets on objectives such as reducing disease after a new contract started in 2004.
In the first year of the deal, earnings rose by a third, breaking through the £100,000 barrier in the process.
Dr Andrew Green, a GP from Hedon, Yorkshire, said the problems experienced by some patients in full-time work in accessing their GPs needed to be addressed in a way that would not impact the care offered to daytime patients.
He said while these patients needed to be served at more convenient times, this should not impact other patients.
"We need to make sure that the costs incurred don't take money from other sources.
"They are going to be people in employment, almost by definition, and to ask them to bear the extra costs seems reasonable."
He said in hospitals people often pay to see consultants privately so they can see them in the evenings or at weekends.
"This choice should extend to patients in primary care," he said.
But Michael Summers, of the Patients Association, criticised the suggestion.
He said: "It is a scandal and it wouldn't be tolerated in any other country."
And Katherine Murphy, spokeswoman for the association, said: "I think it is naive to assume only people that are in employment will need to access a GP out of hours.
"GPs should make themselves more available outside normal working hours, the service is obviously not matching what patients want and this is the reason why this situation has now arisen.
"It is already hard enough to see a GP and people are having to go to A&E for out of hours care."
A Department of Health spokeswoman said: "We will never change the values of the NHS - universal, tax funded, free at the point of need.
"Let's be clear - nobody should have to pay for these services."
And Dr Hamish Meldrum, chairman of the BMA's GPs committee, said the proposal did not echo the views of the association as a whole.
"BMA policy is against patient charging"