A single person on welfare can no longer afford to rent in Australia's cities and would need 150 per cent of their income to live in Sydney.
The Rental Affordability Index, released on Wednesday, has painted a bleak picture for pensioners, single parents and those on welfare, who are being squeezed out of the nation's capitals.
For a single person on benefits, living in Australian cities is described as "untenable", and in many city postcodes, rents amount to more than 100 per cent of Newstart welfare payments ($17,400), or 150 per cent in greater Sydney.
Households paying 30 per cent of income on rent are at the critical threshold level for housing stress, the report says.
The nation's average rental household currently spends around 29 per cent of income on rent in Sydney, 28 per cent in Hobart, 25 per cent in Brisbane and Adelaide and 24 per cent in Melbourne.
That means a renting household earning less than $90,000 in Sydney or $84,000 in Melbourne would be in housing stress.
In metropolitan areas, which is where one-bedroom dwellings are generally available, about 60 per cent or more of a single pensioner's income ($26,600) would be spent on rent, the report says.
The most unaffordable city is Sydney, which would require 97 per cent of a person's pension, the ACT next-highest at 73 per cent.
And a single parent working part-time and on benefits would find the major capitals "extremely unaffordable", needing to spend 71 per cent of their income ($38,000) on rent in Sydney, 59 per cent in the ACT and 58 per cent in Melbourne.