While planning committees are supposed to reach a decision within 13 weeks, NAO research suggests that applications for major residential schemes take an average of almost 26 weeks to approve.
Moreover, the research claimed a scheme can take almost two years from initial discussion with the local authority to construction work actually beginning on a building site.
This comes despite the government setting aside a£68m-a-year pot for councils to speed up planning applications.
Government figures on processing planning applications for large housing developments appear to show significant improvement, with 67% of decisions being reached in 13 weeks in 2007-08, up from 37% in 2002-03.
But the chairman of the Committee of Public Accounts, Edward Leigh (Con) MP, said councils massage their figures simply by rejecting a large number of applications.
NAO head, Tim Burr, said: “The government has given local authorities a greater financial incentive to reach quicker
decisions on planning applications, with more decisions on major housing schemes now being taken within 13 weeks than five years ago.
“Whether the speed of development has increased is less clear. The government should use the data collected by the NAO as a benchmark for assessing its future effectiveness in improving the planning process.”