Australia hosts significant quantities of illicit funds from outside the country, according to the 2015 Financial Secrecy Index.
The Tax Justice Network's index, released every two years, rates countries based on financial transparency. The latest index rates Australia 44 out of 100 (47 in the previous survey) so it must make "major progress" in offering satisfactory financial transparency. 
The index also shows that the United States, third on the list, has overtaken countries that have traditionally been used by multinationals and wealthy individuals as tax havens, ahead of Singapore (fourth), Cayman (fifth) and Luxembourg (sixth).
The Tax Justice Network said the US was "the jurisdiction of greatest concern" and was "posing serious threats to emerging transparency initiatives ... The US is one of the few whose secrecy score worsened after 2013," the Tax Justice Network said in a statement.
Switzerland stayed at the top of the index, followed by Hong Kong.
"Despite what you may have heard, Swiss banking secrecy is far from dead, though it has curbed its secrecy somewhat," TJN said.
It said Britain also remains a huge concern, with its jurisdictions - the Overseas Territories and Crown Dependencies - still operating "in deep secrecy".
The report said Australia had taken significant steps to address tax evasion and tax avoidance, especially to stem revenue loss from Australia. "However, its record of helping other countries combat tax evasion and money laundering is somewhat mixed," it said.
"A number of recent cases demonstrate that Australia undoubtedly hosts significant quantities of illicit funds from outside the country."
Tax Justice Network's report said, overall, when seeking to tackle illicit outflows from Australia, including the protection of tax revenue, "Australia has taken an innovative and highly proactive approach". It referred to the ATO's Project Wickenby taskforce, which under the Coalition government has now been replaced with the Serious Financial Crime Taskforce.
It also referred to former Treasurer Joe Hockey's legislation to stop multinational profit shifting, and Australia's decision to sign up to the OECD Common Reporting Standard for the automatic exchange of financial information.
The report said that due to the nature of illicit financial flows, comprehensive data was not available. It instead referred to recent media reports by Fairfax Media regarding Australia's role as a safe haven for corrupt funds.
It said in 2007 the then Labor government released draft legislation to extend anti-money laundering provisions to real estate agents, dealers in precious metals and stones, lawyers, accountants, Australia notaries and company service providers. But the legislation was never implemented.
In   April, the Financial Action Taskforce released its latest mutual evaluation report of Australia's anti-money laundering and counterterrorist financing system.