Global tax experts KPMG expect taxpayers throughout the world will need to pay more tax in the years ahead as governments repay debt and fund increases in social welfare.
In its annual global tax rates survey released on Tuesday it says Australia's tax mix is out of step with global averages.
Australia has heavier direct taxes - like corporate and personal income - and lower indirect taxes - such as GST - than the global norm.
The average corporate tax rate is 23.68 per cent compared with Australia at 30 per cent while the average VAT rate is now 15.79 per cent compared with Australia's GST equivalent of 10 per cent.
KPMG Australia National Managing Tax Partner David Linke says the study from information from 145 countries shows that indirect tax rates have a natural optimum range between 15 per cent and 20 per cent.
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"In the medium term, most countries will settle on a rate in this range," he says.
"Australia's current GST rate and relatively thin base will also come under increasing scrutiny."
He says that while tax rates in general are not changing fast, governments are moving to widen their tax base, increasing the range of goods, services and activities that can be taxed to bring in more revenue.
However, raising income taxes is increasingly difficult in an inter-connected international economy and corporate taxes will fall as tax competition increases, Mr Linke says.
The Turnbull government is in the middle of a tax review white paper, which it has repeatedly said has all tax options on the table.
