Of 22 programmes in England and Wales that are currently listed on www. governmentfunding.org.uk, a website run by the Directory of Social Change, the average maximum grant length from government departments is 2.8 years.
The training and publishing organisation analysed the information on its site and found eight programmes had maximum grant lengths of one or two years and only six were available over periods longer than three years.
Ben Wittenberg, director of policy and research at the DSC, said the figures showed that three-year funding was still not the norm, despite ministerial pledges. "The big thing is that the times stated are the maximum terms rather than the actual amount of time the grant will be available for," he said.
"With a lot of the programmes this is sensible - there is no need for funding to refurbish a war memorial to be available over three years. But there is a danger that we look to three-year funding as the answer to everything - and it's not."
Louisa Darian, policy officer at umbrella body the NCVO, said ministers had talked up three-year funding, but it was not appropriate in all cases. "It will be interesting in, say, October, when government departments will have to explain exceptions to the three-year rule to the Office of the Third Sector," she said.
Kevin Curley, chief executive of local umbrella body Navca, said the figure was better than he had expected. He added that three-year funding was important. "We argue for three years because this gives the public the best and most cost- effective services," he said.
An OTS spokesman said: "Our commitment was in relation to the government spending round that began on 1 April this year, so it won't be reflected by existing programmes.
"Government departments will report their progress to the third sector minister in the autumn, and his findings will be published as part of the Compact review later this year."