The organisation said it was spending about £13 per call to cover staff costs, but receiving £7 to £8 per call from CCGs. NHS Direct previously operated its NHS telephone service at a cost of £20 per call.
Earlier this month, NHS Direct said it planned to withdraw from contracts in North Essex and Cornwall, where services are yet to go live.
Now it will pull out of its remaining services in Somerset, Buckinghamshire, east London and the City, south-east London, Sutton and Merton, West Midlands, Lancashire and Cumbria, Greater Manchester, Merseyside and Cheshire.
GPC chairman Dr Chaand Nagpaul said the announcement revealed 'worrying flaws' in NHS tendering and contracting processes.
NHS England said it would support CCGs and oversee the transition of services to new providers.
Ministers and NHS bosses are understood to favour handing the failed contracts to ambulance trusts. But GP out-of-hours providers have said they are best placed to take over.
Not-for-profit out-of-hours groups largely lost out in tendering, with most contracts awarded by commissioners to ambulance trusts, NHS Direct and commercial providers.
Dr Gill Clements, medical director at Shropdoc in Shropshire, said: 'NHS England is going to re-procure the service and it looks as if it may amend the specification. This is going to start towards the end of next year and Shropdoc will be interested in bidding for that work.'
Shropdoc, which is handling out-of-hours 111 calls in the region after NHS Direct failed to launch its service properly, has offered to take over the contract in the interim.
Dr Mark Reynolds, chairman of Urgent Health UK, an umbrella body for GP co-op successor organisations, said ministers should support out-of-hours providers to take over NHS 111. It was widely accepted, he said, that 111 was run best by not-for-profit GP out-of-hours organisations, and the government should offer flexibility for GP groups to take on contracts dropped by NHS Direct. Dr Reynolds said his organisation, IC24, would look to form alliances with other providers before considering bidding.
Dr Zahir Mohammed, medical director at Bardoc in Greater Manchester, said his GP group was discussing a possible consortium.
'We originally bid before it went to NHS Direct,' he said, 'so there are discussions around a further bid.'