The value of investments owned by the largest fundraising charities fell by more than a fifth during the recession, according to research by Cass Business School.
The research, carried out by Cathy Pharoah, professor of charity funding at Cass, found that the total value of investment assets held by the UK's 500 largest charities fell by £1.5bn, or 21 per cent, between March 2008 and March 2009.
Investment income fell by 8.4 per cent, from £506m to £484m.
"Many of the major service-providing charities rely on investment income to provide a cushion, or an independent source of income, against fluctuations in their income," said Pharoah. "A fall in the value of their assets makes it much harder for charities to plan future activities or commit to developing much-needed new services."
The research was released in advance of Charity Market Monitor, a survey of the top fundraising charities, which is expected to be released in June.