Reform also suggested that prescription fees from £7.85 to £10, and doing away with exemptions for the elderly and pregnant women. A means-tested system could also mean that terminally ill patients end up paying for end-of-life care.
The cash generated, it says, could be used to improve services such as weekend doctor's surgeries, and that fees are 'unavoidable' for a health service that is struggling to care for an aging population.
According to the Daily Mail, it is estimated that the NHS will have annual debts of £30 billion, and a poll during the summer revealed that half of GPs are in favour of a fee-paying system for appointments.
Thomas Cawston, research director at Reform, said: "The Government must find a way of generating more money for the NHS. We currently have a system which is very generous.
"A lot of people who are reasonably well off wouldn't mind paying £10 for a GP appointment on a Saturday morning, for example."
Mr Cawston added: "Few will want to debate higher NHS charges but the funding outlook for the service makes it unavoidable. Prescription charges are the easiest route to new revenue, with exemptions for people on low incomes built in."
Around two thirds of Western European countries already charge patients to see the doctor, while half pay for hospital visits or stays.
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