The not-for-profit sector is under mounting pressure to publicly disclose how all donated funds are spent.

Figures from Givewell, an organisation researching charities' income and expenditure, showed the average fundraising cost in 2009 was 19 cents in the dollar.

However fundraising costs vary between charities. Figures provided by Givewell showed that the Australian Conservation Foundation, which raised $11.1 million from donors in 2009, spent 43¢ in the dollar raising money.

The Australian Red Cross raised $44.48 million, and spent 35¢ in the dollar raising fundraising. RSPCA NSW used just 8¢ in the dollar to raise more than $20 million.

Charities also vary dramatically in how much they tell donors about fundraising costs because there is no Australiawide standard of reporting how the money is spent.

Some charities provide detailed information in annual reports, many of which are available on the internet, while others make no cost breakdowns available. Expenditure includes the cost of publicising appeals, staging events, printing publicity material as well as administration costs such as wages and hiring professional fundraising companies to collect money.

Australia has more than 40,000 registered non-profit fundraising organisations, employing more than 630,000 paid staff and using 4.6 million volunteers. The sector has a total income of about $81 billion, close to half of which comes from government.

Consumer group Choice said there was a need for better disclosure because charities all use different accounting measures.

The call for greater charity transparency comes after the South Australian government introduced regulations last month allowing donors to check how much of their money goes towards wages and administration. Charities must publish details on the government's charities' website.

In NSW there is just a requirement to cap fundraising expenses under 40¢ in the dollar.

The McGrath Foundation, founded by ex-Test cricketer Glenn McGrath and his late wife Jane to help pay for breast cancer nurses in rural and regional areas is one of many charities that does not provide fundraising costs on its websites. The Foundation reportedly raised $9.5 million last financial year and received a $12 million federal grant in late 2008. Each of the 55 nurses it funds costs about $300,000 to $350,000 to over a three-year period. The Foundation did not return The Sun-Herald's calls.

Chris McMillan, chief executive of the the Fundraising Institute Australia (FIA), the sector's peak professional body, said one charity might count marketing activities as a cost of fundraising, while another charity wouldn't. ''You are not able to compare apples with apples,'' she said. ''But people are sensible enough to know that charities are run as businesses … so there will be some costs of staffing and overheads.''

Wendy Scaife, with the Centre of Philanthropy and Nonprofit Studies at the Queensland University of Technology, said charities have to invest in trying to attract more donations.

''It's the organisations that are not spending enough on their admin and fundraising that are more of a worry,'' she said. ''

Peter Holdsworth, who provides management support to charities though his consultancy Pathways Australia, said the nature of the charity's cause affects how much it needs to spend to raise funds. Some organisations are more attractive to donors than others, he said.