But the college was accused of lacking ambition over improving access for unsatisfied patients.
RCGP chairwoman Dr Maureen Baker told health policy leaders on Thursday that independent research commissioned by the college calculated the costs of 8am to 8pm, seven-day routine services across one in four practices at £749m per year, rising to £1.2bn to cover half of practices.
The calculations were extrapolated by the college from research by the Deloitte accountancy firm.
‘Contrast this with the limited one-off funding of £150m for extended hours provided through the GP Challenge Fund and you'll see the sort of gap we are talking about,' said Dr Baker.
Funding currently ‘on the table may go some way to plugging’ the gaps in existing services, the college chairwoman said, but ‘will certainly not allow us enough resources to open surgeries in England 8 to 8, seven days a week for fully routine care’.
The government has pledged to provide evening and weekend services for every patient in England by 2020, although ministers have made clear not every practice will have to open seven days.
NHS England has so far refused to release details of its estimated costs of introducing a seven-day NHS.
Seven-day GP services
Dr Baker was challenged during the Westminster Health Forum conference in Whitehall over her suggestion that patients were generally happy with access currently provided after she cited the NHS GP patient survey showing 75% satisfaction with opening hours.
Dr Ivan Bennett, clinical director of Central Manchester CCG, which has been piloting extended access since 2013, said the figure was an ‘indictment’.
‘Are you happy that one in four people cannot sign up to the fact that they are content with their GP opening hours?’ he asked. ‘We must have better ambition than that.’
Dr Baker replied that 75% satisfaction was ‘in fact pretty high’, and 100% would never be happy.
‘We would love it to be better, that's why we need, actually not 5,000 GPs by 2020 but 8,000 more. We have a workforce that is stretched as thin as can be and if we try to stretch it further holes appear in the fabric and it breaks down,' she added.