Weighing into the debate about corporate tax dodging, the owner of Harvey Norman told Fairfax Media he could "dramatically reduce" his company's tax bill by shifting profits overseas but chose not to.

Harvey Norman had 15 stores in the low-tax jurisdictions of Ireland and Singapore.

"We've got an opportunity to dodge a lot of tax but we don't because it's morally wrong," he said.

His comments followed a similar attack by Wesfarmers chief executive Richard Goyder, who this week called on Australian companies to "pay tax in the communities in which they operate".

Treasurer Joe Hockey, who made the closure of global tax loopholes an aim of Australia's G20 summit next month, insisted on Wednesday the government was doing "everything we can … to ensure that companies that earn profits in Australia pay tax in Australia".

Many businesses and the Corporate Tax Association, which represented much of the S&P ASX 200 companies on tax matters, insisted there were legitimate reasons why corporate tax contributions often came in below the statutory 30 per cent company tax rate but both sides of politics agreed this week that more should be done to prevent taxable earnings flowing overseas.

On Tuesday, Fairfax revealed a report by the inspector-general of taxation Ali Noroozi that identified $270 billion had flowed between Australian companies and their offshore subsidiaries and raised concern that the Australian Tax Office had not been equipped with specialist staff to tackle the so-called transfer pricing issue.

Mr Harvey said he would not criticise competitor businesses, some of which according to a report released this week paid as little as 10 per cent or 15 per cent in company tax, based on profits reported over the past ten years.

But he added: "We all have to decide what we think is right and what is not."

Mr Harvey said the governments of countries with lower company tax rates were "constantly" trying to convince his company to relocate its headquarters overseas to minimise tax liabilities.

James Hardie was based in Ireland for tax purposes. It operated a string of subsidiaries in tax havens, including Bermuda, and the tax report Who Pays For Our Common Wealth? found it had effectively paid no tax in Australia over a decade.

Harvey Norman's Irish stores were running at a loss but Mr Harvey said the company had not shifted profit from Australia to reduce its local tax bill. According to the report, Harvey Norman paid an effective tax rate of 31 per cent.

Based on a decade of pretax profits, the company had paid $3.5 million more than the 30 per cent rate.

Mr Goyder, who was chairing the B20 summit of the world's biggest corporations, said companies that avoided paying taxes ended up damaging their own reputations.

"I think the conversation will head from whether [tax avoidance] is legal to whether it is ethical, and I think that change in debate is right," he said.

The Greens are confident of securing support in the Senate on Thursday to establish an inquiry into tax avoidance by Australian corporations with specific reference to whether existing laws are sufficient and the performance of the ATO.

Earlier this year, Fairfax Media revealed insignificant rates of taxation paid by Google, Apple and Ikea on Australian-derived revenue.

On Wednesday, Mr Hockey said he would not single out multinational tech companies by name but said the differential between what consumers in other countries paid and the higher price Australians paid for certain products meant there should be "taxable income" that stayed in Australia.