The Labor-aligned McKell Institute's report, Mapping Opportunity: a national index on wages and income, found the income gap is widening and that the opportunity to earn differs markedly across the country's 150 federal electorates.

And it found that along with the traditional drivers of social mobility, such as education and training, and locality, access to the internet has emerged as a "key determinant" of socio-economic opportunity.

Last year, Treasurer Scott Morrison rejected repeated Labor claims that inequality in Australia had reached a 75-year high.

"The latest census showed on the global measure of inequality, which is the Gini coefficient, that is the accepted global measure of income inequality around the world and that figure shows it hasn't got worse, it has actually got better," Mr Morrison had said.

However, two independent fact-checking exercises by the university-run website The Conversation and by RMIT-ABC tended to support the claim that inequality had risen since the 1960s even if it was higher a few years ago than it is now.

The Mapping Opportunity report found the greatest "access" to income for working age Australians tended to be concentrated in the affluent inner-city electorates where education levels and employment variability are higher on average.

In fact, 11 of the top dozen electorates nationally, in terms of income accessibility, were government-held seats with the highest level being recorded in the federal Liberal seat of North Sydney.

The only non-Liberal exception in the top 12 was the Greens-held electorate of Melbourne.

By contrast, 7 out of the bottom dozen electorates, where access to income was found to be the lowest, were held by Labor.

Of these, Wakefield on Adelaide's far-northern fringe where GM Holden was once the major employer, rated lowest of all 150 seats.

The McKell Institute's director, Sam Crosby, said the finding points to a longer term malaise in Australia's social and economic fabric because it challenges the so-called "fair-go" principle upon which we believe our society is built.

He said it was important to see the growing span in income inequality "not only through the prism of wage stagnation but through the longer-term prism of social mobility".

That meant that securing stronger wages growth, while important in the immediate term, would only constitute part of the solution, with spending on the "infrastructure" for opportunity to overcome geographical and class disadvantage, offering the longer-term answer.

"People want a fair go for their kids, not just extra dollars today," he said.

"Access to internet has risen to be a key determinant in accessing good employment and electorates like Lingiari (NT), Fowler (NSW), Parkes (NSW), Blaxland (NSW) and Werriwa (NSW) have over 8000 people on average in each electorate who have no internet access in their dwellings.

"We should be concerned with ensuring Australians have access to the things we know improve social mobility: education, access to the internet, English proficiency, family employment circumstances.

"Australians have never bought the pure socialist argument for equality of means, but they have strongly supported equality of opportunity."

Mr Crosby said the research showed these were the forces pulling at Australia's wealth distribution exacerbating unfairness and resulting in the middle class being stretched.

But while the prospects of some areas in regional Australia looked bleak, there were also seats where the report found positive indicators for future social mobility including Parramatta, Melbourne, Adelaide, Griffith (QLD), Sturt (SA), Barton (NSW), Wills (VIC), Menzies (VIC), Chisholm (VIC), Bennelong (NSW).

"All are in the top 30 electorates according to the social mobility indicators but are not in the top 30 for median income, so they all have a very good chance of moving up in terms of income," Mr Crosby said.

The most advantaged electorates (potential wages)

North Sydney, NSW

Kooyong, Vic

Bradfield, NSW

Higgins, Vic

Bennelong, NSW

The least advantaged

Wakefield, SA

Lyons, Tas

Brand, WA

Braddon, Tas

Longman, Qld

Source: McKell Institute - Mapping Opportunity