The NHS is unlikely to be free at the point of use within 10 years, say doctors.
NHS charges is a topical issue
A British Medical Association poll of 964 young GPs and hospital doctors found 61% thought patients would have to pay for some treatment by 2017.
Nearly half of all young doctors also expect to leave the NHS within 10 years, according to the survey.
All three main political parties have ruled out bringing in a form of charging in the short-term.
The doctors questioned were members of the BMA's Junior Members Forum, which amongst its members are the top are doctors of the future as it includes those who have graduated within the last 12 years and students.
The poll also revealed 94% thought the role of the private sector would continue to grow.
A total of 48% of those questioned said they envisaged they would have left the NHS within 10 years, with only a third (35%) of those saying that would be through choice.
Forum chairman Dr Andrew Thomson said it was time to have a debate about the future of the NHS because of pressures from the ageing population and new, ever-more expensive drugs.
"Doctors fear that current reforms are damaging the NHS beyond repair.
"We seem to be selling off the service to the highest bidder without considering the legacy for future generations of patients.
"Government reforms are having negative effects on both services and the morale of doctors. We need to find ways of moving the NHS towards a period of stability. At the moment it is under serious threat.
"We will be the ones making the decisions in the future and implementing changes so we want to know what the public, profession and political parties think."
Various options have been put forward, including asking patients to contribute towards the cost of some minor treatments, such as varicose veins, or excluding them from NHS care altogether.
There has also been suggestions that an NHS tax could be introduced to help pay for the extra demands on the health service.
Dr Thomson said his members were not expressing a favour for any one option, but he suggested patients may well be ready for a change in the system.
BMA policy is still that the NHS should be free at the point of need, although the issue is likely to be discussed at the doctors' annual conference, which sets policy, later this year.
But a spokeswoman for the Patients Association said: "I think it is an important principle that where care is needed it is free.
"We would not be in favour of patients paying for care where doctors say it is necessary."
The Department of Health has defended NHS reforms, saying it is committed to creating "a truly patient-led service".
"What will not change is our commitment to a universal, tax-funded service, with equal access for all," said a spokesman.