Individual donations to charities could fall by £20.5m a year if 5 per cent of public sector staff lose their jobs, according to research by media agency Mike Colling and Company.
Using data from the TouchPoints SuperHub Survey for 2010, which included responses from a cross-section of 28,000 adults in the UK, the research looked at the impact that public sector job cuts could have on charitable donations.
MC&C's research says that public sector employees make up 20 per cent of the UK population, but give 38 per cent of donations from the public and private sectors combined.
Using the estimate of the Chancellor, George Osborne, that 490,000 public sector employees could lose their jobs, it calculates that this would result in a loss of 5.1 per cent of existing income from public sector charity giving, or £20.5m a year.
The research says mental health, overseas relief, the underprivileged and arts and national heritage are the sectors public sector employees are most likely to donate to.
Mike Colling, managing director of MC&C, said charities should think about their strategies for donors losing their jobs.
"They are likely to be your core supporters - you should still treat them as supporters without asking them for money for a while," he said. "When they are back in work, they are more likely to come back."