The nation's postal service heads a list of government-owned enterprises the national commission of audit says should be privatised.
Others on the sell-off list include the Snowy Hydro, the Royal Australian Mint, and the National Broadband Network (NBN Co).
The commission says significant capital, about AU$13 billion, is locked up in government-owned bodies.
While the states had been busy selling-off some of their assets, especially electricity generators, the issue of privatisation had been largely dormant at the federal level, it said.
The commission cites a rapid decline in letter volumes as one of the reasons for not needing Australia Post to be held in public hands.
It recommends the corporation be sold-off after 2016, three years after the UK went down the same path with Royal Mail.
The commission did not nominate a specific timetable for privatising NBN Co, but it did note provisions were already in place.
In the short term (2014-2016), it wants to see Snowy Hydro, Australian Hearing Services, Defence Housing, and the Australian Submarine Corporation sold.
After 2016, it has listed the Australian Track Corporation, Moorebank Intermodal Company, and the mint.