Half of people are put off from giving because they think charities are not clear about how donations are spent, new research by the consultancy nfpSynergy suggests.
The online survey of 1,031 British adults, carried out in July and published today, also found that 61 per cent said that "too little money going to the cause" was their reason for not donating.
Respondents were asked what were the main factors that deterred them from giving to a particular charity. They could select up to five from a list of 11 options.
Forty-seven per cent of respondents chose charities spending too much on staff salaries and 43 per cent selected fundraisers being too persistent.
Just over a third, 34 per cent, said they were put off by fundraising methods being "too intrusive".
Twenty-eight per cent selected spending funds on big campaigns or advertising and a further 33 per cent would be put off by bad publicity about the charity.
Donors were asked whether charities should spend as much of their donation as possible this year, or if it made sense for charities to spend more of the money on fundraising this year if it would increase their income in future.
Fifty-one per cent of people said those charities should spend as much of their donation as possible on current needs compared with 43 per cent who said they were happy for more to be spent on fundraising.
Joe Saxton, co-founder of nfpSynergy, said the survey results showed that people want to know how their donations are spent. "Charities should sing from the rooftops about what they spend their money on," he said. "It’s time the sector stopped huffing and puffing and bit the bullet.
"We recently called for an easy way to find out how much of their income charities spend on what they’re fighting and campaigning for. If charities want to increase donations and maintain the donors they already have, action should be taken – and quickly."