The Tax Office is ramping up its offensive on corporate tax dodging, setting its sights on a record number of audits of large or multinational businesses suspected of shifting profits overseas.
It has also announced it will open hundreds of reviews into rich Australians and small companies with offshore accounts in tax havens or low-tax jurisdictions such as Singapore.
The push comes as the OECD plans to launch a suite of new international tax rules at the G20 meeting of finance ministers in Moscow on Friday, in the latest effort to plug loopholes and shore up government revenues.
The ATO unveiled its key focus areas as part of its annual compliance strategy for 2013-14. The strategy includes 250 reviews and 70 audits of large or multinational businesses operating in Australia, of which at least half relate to suspected profit shifting.
The strategy also includes 680 reviews and 115 audits of individuals and small enterprises suspected of using secrecy jurisdictions to avoid tax.
Second Commissioner Bruce Quigley said profit shifting remained a key focus for the Tax Office due to it being one of the greatest threats to the country's tax base. Large businesses (with an annual turnover of $250 million or more) contribute 68 per cent of Australia's corporate and superannuation fund tax.
"Because of the size of these transactions and the size of the companies we are looking at, it's of big consequence for the revenue of Australia," Mr Quigley said. "It's globally the No.1 issue that revenue authorities are dealing with."
Trusts will also face scrutiny, with a new taskforce homing in on companies exploiting a perceived weakness in trust law for financial gain.
Australia has followed other governments, including Britain, the US and France in scrutinising the corporate structures of large multinationals. Earlier this month, it launched a taskforce to establish the purpose of Australian businesses in low-tax jurisdictions.
The focus on wealthy individuals follows the leaking of personal tax records to the International Consortium of Investigative Journalists in Washington last year. It also reflects information obtained by the Tax Office more recently through co-operation with other jurisdictions.
"In our conversations with other countries, we are identifying more Australians linked to entities set up offshore," Mr Quigley said.
The Tax Institute's Robert Jeremenko said scrutiny of common corporate structures, such as trusts, required clearer explanations of the law.
In 2012-13, the ATO raised $2.19 billion in unpaid taxes after conducting audits of 519 large businesses.
Tax office targets
■ Rich Australians
■ Tax havens