Some GPs report waiting more than a year for payments, while others say they have made multiple calls to the support service and some say they have sent 'upwards of 20-25 reminder emails' asking for payment.
Across 35 practices that have contacted pressure group GP Survival to join a bid to claim payments via a debt collection service, unpaid amounts claimed range from £40,000 to £500. The average amount outstanding is around £10,000.
Both NHS England and Capita have urged practices to seek to resolve problems with payments 'through normal channels'.
A spokeswoman for NHS England said: 'Any GP who has a payment concern should contact Primary Care Support England in the first instance. This will enable them to resolve any outstanding actions required.'
A spokeswoman for Capita said the organisation was trying to make contact with GP Survival to 'start dialogue'. She said: 'We are fully focused on resolving any isolated individual queries as swiftly as we can. We have established processes for dealing with individual queries and would encourage GPs to contact us through the usual channels.'
However, GP Survival chair Dr Matt Mayer said that of the 35 claimants 'all have tried' to seek payment by contacting the primary care support service, but that they had been passed between departments, given multiple 'case numbers' or had found themselves unable to speak to anyone within the service who could help.
'We're having a more detailed meeting with the collection agency this week to discuss the most legally efficient way to proceed,' he said.
GPC deputy chair Dr Richard Vautrey told GPonline that the BMA and LMCs were also ready to help practices struggling to resolve problems with late payments.
Primary care support
'It is completely unacceptable that any practice is still owed money,' he said. 'When we have been made aware of any issues, we have raised that with senior managers and resolved claims.
'Practices that have raised issues with us we have taken up straight away and I am not aware of any still outstanding.'
The BMA published advice earlier this year on how practices that had suffered clear financial losses because of problems with the primary care support service run by Capita could claim compensation. NHS England was not able to say whether any practices have received compensation through this process to date.
Dr Vautrey added: 'We have made aware to LMCs the route to claim for a demonstrable loss – if practices have used that and not had redress they should notify us.
'It is being used by a small number of practices. If there is outstanding money owed that should be paid straight away. If they have had to take out a loan that should be paid for and compensated for. NHS England should and will do that, but individual practices need to use the route we have set for them.'
Dr Vautrey said that Capita needed to be clear it was taking action to resolve problems with payments, and said that a GP practice 'would have been closed down years ago' if it had problems on the scale experienced with primary care support.
Capita describes the payment system it inherited when it took control of the primary care support service as 'highly localised, non-standardised and inconsistent' and attributes some delays to this as well as to the fact that it relies on third party organisations for some data that allow the primary care support service to process payments.