Australia had $677 million of unclaimed money in bank accounts, shares and insurance policies in 2012, according to the MoneySmart website of the Australian Securities and Investments Commission.

Sources close to the inquiry said its final report, to be delivered to Treasurer Joe Hockey next month, might recommend these funds be deployed into a trust that could then fund social impact bonds, new instruments where financial returns are linked to social benefits. This sector is expected to grow to $32 billion in Australia within a decade.

Using unclaimed monies for social impact investment was a key recommendation of a report released last month, titled "Impact Investing: The Invisible Heart of Markets", published by the Social Impact Investment Taskforce, which was established last year under the UK Presidency of the G8.

UK Prime Minister David Cameron has been a champion of social impact investing, which he sees as a way to relieve the government balance sheet of the full cost of providing social services.

Rosemary Addis, co-founder and chair of Impact Investing Australia and Australia's representative to the taskforce, said bringing a $350 million social impact fund to market was a key plank of the Australian strategy, and governments would play a critical role in identifying appropriate ways to capitalise the fund.

"It would be a terrific result to have the financial system inquiry recommend a social impact fund and point to sources of capital such as unclaimed assets that government could appropriately consider to make a capital contribution to that type of public good," she said.

Members of the Social Impact Investment Taskforce – the G8 countries along with Australia and the EU – will meet in Rome on Tuesday and Wednesday to focus on the role governments can play in facilitating impact investment.

The interim report of the financial system inquiry highlighted the potential of social impact investment, which Impact Investing Australia estimates will grow to at least $32 billion within 10 years.

"A number of submissions have responded positively to policy options put forward in the interim report, including an active role for government in market development and the important contribution a social impact fund or bank could play as part of the financial system in Australia," Ms Addis said.

Impact Investing Australia was established early this year in response to an industry identified need to provide leadership, demonstrate demand and remove barriers to the impact investing market.

Last week, the group announced Daniel Madhavan had been appointed its inaugural CEO. He joins from Goldman Sachs JBWere, where he was chief operating officer and most recently, acting CEO.

"Australia faces some significant challenges around how to adequately fund our social services, and helping to find innovative solutions to this is an exciting challenge," Mr Madhavan said.

UK venture capitalist Sir Ronald Cohen, who chairs the Social Impact Investment Taskforce, told the Financial Times last month it was up to governments to take advantage of the surge in interest in impact investing.

"Investors want it. Entrepreneurs want it. So the role of government is very important. Governments need to play an enabling role," he said.