The research, by think-tank Planning Futures, analysed capacity in planning departments across the country and found that the majority are struggling to provide an effective service.
The think-tank said that the findings show that "the majority of planning departments in England are in significant decline and struggling to provide an effective and robust planning service".
On average, council planning departments had lost 15 per cent of staff in a decade, it found, but 51 per cent of councils had experienced larger losses, according to a report of its findings.
Losses were greater in planning policy teams than development management, with average losses of 18 per cent and 13 per cent respectively.
The survey found that some departments had coped better than others. While some departments reported that cuts of up to 20 per cent in their staff were "manageable", others reported times when their services were nearing the point of collapse, despite more modest cuts.
The report recommended that local authorities should be given autonomy to set their own planning fees so that they can recover the full costs of the development management process.