The Turnbull government's pledge to reduce personal income tax comes at a time of the slowest wage growth in at least 20 years.
But a new report also shows Australian workers are wearing the biggest proportion of the national tax take by far, and the second highest in the world behind Denmark.
Organisation for Economic Cooperation and Development (OECD) figures show personal income tax makes up around 40 per cent of the country's revenue.
Company tax as a proportion of revenue is smaller at 15 per cent, but is still the third highest among OECD countries.
The OECD's revenue statistics 2017 report, released on Thursday, also shows GST is just 13 per cent of total revenue and stands 33rd in the 35-country OECD bloc.
The Paris-based institution has long urged Australia to take the pressure off personal and company taxes by either raising the GST rate, broadening its base or both.
However, such advice has been ignored by successive governments with the rate having been at 10 per cent since the GST's inception in 2000 and food, health and education remaining exempt from the impost.
Still, the report also shows government revenue generated in Australia as a proportion of GDP is below the OECD average and ranked 28th out of the 35 OECD countries.
Malcolm Turnbull flagged this week personal income tax cuts would be the focus of next year's May budget.
Labor has criticised the announcement, saying the prime minister is trying to divert attention away from divisions in his own government and if he was serious about lowering taxes he wouldn't go ahead with the Medicare levy increase.
