Large trusts and foundations gave out more money in the period leading up to the start of the recession, despite a decline in their income, according to the Directory of Social Change.
The 12th edition of The Guide to the Major Trusts, which was published last month, reveals that the 400 largest trusts in the UK awarded a total of £2.53bn in 2007/08, compared with £2.3bn the previous year.
The increase came despite a £126.6m fall in their combined income and about £4bn being wiped off the value of their assets.
"Most trusts are maintaining their level of spending, at least in the short term, and would rather dip into their reserves if necessary to support their beneficiaries, who are largely small to medium-sized charities," said Tom Traynor, co-author of the guide.
Much of the increase in grants can be traced to The Wellcome Trust, whose awards increased from £324m to £598m.
A DSC spokesman said: "These figures are from the start of the economic downturn, so the full picture of how the recession has affected grant-making from these funders may not be clear for several years.
"However, DSC research suggests that grant-makers want to shield their beneficiaries from the worst effects of the recession."
The guide is in two -parts: volume 1 gives details of the top 400 trusts; volume 2 gives details of a further 1,100 grant-makers. They cost £65 each or £90 for both.