The latest Productivity Commission's on housing shows the ACT also had the highest rates of all people claiming the payment who were paying enough rent to claim the maximum payment available, indicative of Canberra's high median rent.

It comes as thousands of new students look to make the city their home ahead of a new university year, entering a housing affordability crisis the head of the ANU Students Association has described as grim.

The report released last week shows 84.7 per cent of those claiming the assistance were claiming the maximum payment available in 2017-18, a figure on trend for the past five years and above the national average of 80 per cent.

It also showed some 86.2 per cent of young people 24 years or younger receiving the assistance, were still paying more than 30 per cent of their income on rent after getting the payment, also above the national average of78.6 per cent.

ANUSA president Eden Lim said the situation facing students in Canberra was grim, and had been steadily getting worse over several years, which the report had confirmed.

She said the association provided many ANU students with help in the form of emergency accommodation and small payments for them to help cover their costs during crises, which had increased particularly in the past fortnight as new students arrived in Canberra.

Ms Lim said the report confirmed housing was essentially unaffordable for almost all students, and it was forcing some students to couch surf with distant relatives or other contacts in town or stay in short term accommodation.

"I suppose what we know it means many students have to work long hours or in unsafe work environments to afford to stay in Canberra, and the financial stress really affects their well-being and ability to complete the course work they came here to do," she said.

She said it was different for every student, the reality for many was that the Commonwealth rent assistance was not enough to cover their costs and most students had to work casually or part-time, and it was also harder for students to compete in the rental market against other potential tenants.

ACT Shelter chief executive Travis Gilbert said the report reinforced findings in the National Shelter's rental affordability index, showing a rise in housing stress by all people receiving social security payments - with Canberra the second-least affordable on most measures.

He said for most of the past decade, median asking rents in Canberra had increased well above inflation, which allowances are linked to, and the index showed the ACT was the most expensive city to rent a detached home in the nation.

"These are properties typically rented as share-houses by young people. In addition, the lower rate of rent assistance payable to sharers further erodes the benefit it offers young people in terms of rent relief," he said.

"We have heard from young people whose lived experience is that paying more than two-thirds of your disposable income to your landlord is the norm, yet the measure for risk of homelessness is 50 per cent."

"It is quite clear that the private rental market in Canberra has priced out people on low to moderate incomes and young people are disproportionately affected as a result."

While the ACT government late last year released a new housing strategy, both the Greens and the Opposition have been pushing for it to urgently implement the proposals, and more fully describe what all them entail.

Housing Minister Yvette Berry last year said she would more fully explain what would be implemented, and when, early this year, though she has promised to boost affordable house sites for sale and redevelop 1000 public dwellings.

ACT Greens MLA Caroline Le Couteur said the report showed the territory performed poorly on several measures, but those worst affected by a lack of affordable housing were Canberra's young people, and they urgently needed the strategy to be implemented.