People will donate more to charity if they make a pledge before receiving an unexpected cash windfall, a study has shown.

New research by experts from the University of Exeter's Business School has revealed that beneficiaries are 25 per cent more likely to give more to if they make a commitment before an unexpected cash boost.

The study showed that people were also 23 per cent more likely to commit to donating to charities if they were asked to do so ahead of receiving any .

The researchers believe that the results could have major implications for future charity fundraising efforts, as it suggests it may be more effective to ask people to commit to donate from any future lottery wins, bonuses or other windfalls before receiving the unforeseen lump sum.

The study suggests that charities could consider including a tick-box for donors to make a conditional pledge, while ethical investment accounts could automatically donate gains that exceed expectations.

The research is published in the Journal of Public Economics.

Dr. David Reinstein, co-author of the study and from Exeter's Business School said: "These findings have real implications for fundraisers who are trying to find the best time to ask someone to commit to giving a donation.

"Charities think carefully about when and how to ask for donations from various sources of income and we have the first evidence suggesting that people are more generous before they know how much money they will receive."

The strongest results came from a study involving 320 UK participants on a web survey platform, who were told they had a 50 per cent chance of winning a £10 bonus.

Some participants—who were told from the outset that they had a 50 per cent chance of winning—were asked to make a conditional commitment to donate to either Oxfam or the British Heart Foundation before learning if they would receive the windfall.

After discovering if they had been successful or not, they could choose whether or not to change their decision.

Other participants took part in the same experiment, with the same odds of winning, but were told if they had won before being asked to donate.

People who were asked immediately before they knew the lottery result were more generous. They were 23 per cent more likely to commit to donate from the winning income, and gave 25 per cent more (when asked to contribute before the outcome of a lottery), compared to those who were asked after they knew they had won.

Dr. Reinstein added: "Actually many finances in life are unplanned or driven by chance—such as wins, inheritances, bonuses or landing a new job with a larger salary; so securing a 'conditional commitment' can be extremely worthwhile for charities and other bodies which rely on public generosity. We're now looking to build on this research and are looking for charities, businesses and government bodies that would like to be involved."

More information: Christian Kellner et al, Ex-ante commitments to "give if you win" exceed donations after a win, Journal of Public Economics (2018). DOI: 10.1016/j.jpubeco.2018.10.009

Journal information: Journal of Public Economics