Almost nine million GP appointments are missed by patients each year, a survey has suggested.
The campaign has led to a reduction in missed appointments
Missed appointments cost the NHS more than £160m a year.
Nearly two-thirds of the GPs questioned in the survey by Developing Patient Partnerships (DPP) backed the idea of fining non-attenders.
GP practices reported that on average, just over 3% of a practice's appointments were missed - a reduction on the figures from last year.
Although the overall figure for missed GP appointments is down by around 3.5 million since last year's survey, 60% of practices still find missed appointments a problem.
Seventy-two per cent also believe they increase waiting times for those people who need GP appointments.
Over two-thirds (67%) of practices think that patients 'forget' their appointment, while 26% think that patients 'feel better' so simply choose not to attend.
The DPP figures also suggest just under four million practice nurse appointments are missed each year.
The DPP and the Institute of Healthcare Management asked just over 700 GP surgeries in the UK to report missed appointments.
It published its survey as part of its annual 'Keep It Or Cancel It' campaign.
The initiative aims to remind doctors and patients what they can do to reduce the numbers of cancellations.
Dr Terry John, a spokesman for the DPP said: "Many GP practices are doing all they can to improve access for patients but still a high volume of appointments are being missed.
"These forgotten millions of missed appointments lead to unavoidable inefficiencies in GP services."
He said patients should let the practice know if they cannot attend an appointment, or if they feel better, so the slot can be used by someone else.
A spokesman for the British Medical Association said: "Anything that helps educate patients to let the surgery know when they cannot attend is helpful."
She said patients sometimes tried to contact GPs to let them know they would have to miss an appointment, but were unable to get through.
"Doctors could help by making sure there is some facility, such as an answerphone, so patients can let them know."
But she added: "The BMA is not in favour of charging patients who miss appointments."
Professor David Haslam, chairman of the Royal College of GPs, said: "Every GP wants to give high quality care with good access. Every missed appointment is a wasted opportunity for another patient.
"Those few patients who repeatedly miss appointments are depriving other patients of care."
But he said GPs could do more to help: "More practices are guaranteeing rapid access, which should make it unnecessary for patients to book a future appointment 'just in case'."
Simon Williams of the Patients' Association said: "These figures clearly show how patient education campaigns like 'Keep It Or Cancel It' have helped reduce the number of missed GP appointments by an impressive 3.5 million.
"While the number of appointments missed remains very high, it clearly shows the effectiveness of initiatives that takes into consideration both doctors and patients."
A spokesman for the Department of Health said: "Patients are right to expect a modernised, responsive and accessible service.
"Increasingly that is the case, with most people now having the opportunity to be seen by a GP within two days.
"But for their part, patients have a responsibility to keep or cancel appointments."