Data from 91 PCTs obtained under the Freedom of Information Act shows just 23 had planned how to use leftover funding from the extended hours directed enhanced service (DES).
Among PCTs that had made decisions, details of how they would boost extended hours were often unclear. The findings also revealed that 11 per cent of PCTs say they have no remaining DES money to pay for increasing extended hours.
The DoH informed PCTs in January that they are expected to spend their full share of the 2010/11 allocation of £161 million on improving GP access.
It called on PCTs to produce plans by 26 March outlining how they would use any remaining DES funding to offer extended hours appointments to patients whose practices were not open outside core hours.
But responses from PCTs received in the six weeks before the deadline show that 62 per cent were yet to make decisions. However, most of these PCTs expected to submit their plans within the deadline.
Meanwhile, 4 per cent of PCTs planned to allow other practices to offer extended hours appointments to patients whose own practices did not offer the service. But details of how these practices would be paid and how medical records would be shared was unclear.
A further 4 per cent said they were looking to expand opening times at practices already offering extended hours, while 2 per cent planned to commission out-of-hours providers to offer bookable appointment slots for routine care. Around 9 per cent of PCTs planned a combination of these schemes.
Dr Nigel Watson, chief executive of Wessex LMC, said the lack of clarity could reflect PCTs' reluctance to spend money on a service they do not consider a high priority.
'A lot of PCTs are also looking at a financial deficit and reducing expenditure.' He added that positive results in surveys show extended opening was not 'as high on patients' priority list as some politicians would think'.
The DoH asked PCTs to draw up plans by 26 March to offer extended hours appointments to all patients.
62% of PCTs are still undecided about how they will offer extended hours appointments to patients whose practices do not open outside core hours.
11% of PCTs have no remaining DES funding for extended hours, but not all practices offer the service.
9% of PCTs plan to implement a combination of measures to increase extended hours opening.
Source: GP investigation of 91 PCTs