Just 50% of GP referrals are electronic currently, but NHS England has launched a drive to push this up to 60% by September this year, 80% by 2017 and 100% by 2018.
But GP leaders warned that plans for patients to leave consultations with a booked appointment in their diary could be undeliverable within a 10-minute consultation.
The £55m cash set aside to incentivise the switch to electronic referrals will come from 'quality premium' cash that CCGs can earn for hitting NHS quality targets.
Details of how practices can earn the cash have yet to be revealed, but huge sums in quality premium funding have been unclaimed by CCGs across England in recent years.
GPonline revealed in January that CCGs missed out on £380m in quality premium payments available for performance in 2013/14 and 2014/15.
NHS officials say the electronic referral scheme aims to 'end hospital referrals by second class post', and set out plans to 'consult on a proposal that by 2018 NHS commissioners and providers will no longer be paid for referrals made by paper'. This could mean adding the requirement to handle referrals electronically to the hospital tariff system.
NHS England director of digital technology Beverley Bryant said: 'For a long time our first class healthcare system has been let down by outmoded systems, where patients are referred to hospital by second class post. We have a duty of care that extends beyond providing effective treatments. We must also provide an effective patient experience that ensures patients feel reassured at a time when they are most vulnerable.'
An NHS England statement on the £55m plans added that: 'Completing referrals electronically allows GPs to book in patients’ hospital appointments right away and offer them a choice of date. Under these plans, patients will leave their GP practice with a scheduled appointment in the diary, ending the days of anxious waits for the post to arrive and frustrating calls to chase hospital letters.'
The statement cited evidence from the National Audit Office that patients are '50% less likely' to miss hospital appointments if they chose the date of the visit themselves, and that the NHS 'could save £51m a year if every referral was made online.'
Wessex LMCs chief executive Nigel Watson said he used the electronic Choose and Book system for referrals 'all the time'.
But he warned that patients often did not want to leave the consultation with an appointment, but instead wanted to be able to go and book it themselves.
'I don't see that in a 10-minute consultation you have the time to give patients a choice of appointments and then book for them.
'Moving to electronic communications has got to be the right way forward. But you can’t expect GPs to sit there and do booking and work as travel agents in a 10-minute consultation.'