Students are facing higher accommodation costs in September as universities raise rents for on-campus residences by the maximum 4pc - or very close to it.
The cap was applied to student apartments last August to ensure rent predictability in the sector, in the same way as it does in Rent Pressure Zones (RPZ).
As campus accommodation rates for 2020-21 are finalised, most universities have also confirmed increases hitting the legal limit.
It has sparked a furious reaction among student leaders.
Union of Students of Ireland (USI) president Lorna Fitzpatrick said: "It's extremely concerning, students are already choosing between eating dinners and paying bills.
"A further increase by these institutions is really worrying for students and their families. They're struggling under severe financial pressure, we have the highest fees in the EU and spiralling rents."
Ms Fitzpatrick said the universities lobbied against the legislation, "so we find it extremely convenient they're using it to increase the rent by the maximum allowed".
All seven traditional universities provide on-campus housing and five have confirmed rents will rise in September.
Meanwhile, decisions are awaited from the other two.
University College Dublin (UCD), Dublin City University (DCU) and NUI Galway are all applying a 4pc rise, University of Limerick (UL) is bringing in a 3.5pc-4pc rise, while Maynooth University is raising rents by 3pc.
Trinity College Dublin (TCD) said: “At present there are no plans to increase on-campus rents. They are periodically reviewed but any changes must be approved by Trinity’s Finance Committee”.
The USI president said she believed a 4pc increase was under discussion at Trinity.
University College Cork (UCC) said: “No decision on campus accommodation rates has been made yet for 2020-21. Student representatives are members of the board that agrees all campus accommodation rates.”
Rents continue to rise despite the addition of thousands of new bed spaces, both on-campus and in purpose-built student apartment blocks off-campus.
In the latter, rents tend to be higher than on campus and students must commit for longer than the typical 38 weeks for on-campus accommodation.
The provision of more students beds is necessary to cater for the ongoing rise in demand, both from the surge in school-leaver numbers and the influx of international students.
Universities defend the rent increases on the grounds they are not adequately funded by Government and they foot the bill – which includes borrowing – for construction and refurbishment.
UCD said it was applying the cap of 4pc a year for each of the next three years in order to secure adequate funding for the maintenance of existing accommodation and the provision of 3,000 new beds, 924 of which will be available in September.
DCU pointed to its ongoing accommodation refurbishment programme, as well as plans for a further 1,240 student bedrooms and that “as there are no grants available for such developments this significant capital investment will be made by DCU itself”.
NUI Galway attributed the rise to increased operating costs and the requirement for “significant investment in the upgrade of the 30-year-old, 764-bed residence Corrib Village”.
UL said it had spent €20m in refurbishing and upgrading campus accommodation over the past five years.
UCD Students’ Union has called for the immediate retraction of the decision to increase on-campus rents.
Clare Austick, NUI Galway Students’ Union president, said they did not know the increases were coming, adding: “We’d be completely against rent increase.
“The rates are extortionate. It really puts pressure on students in terms of some having to work more than one job in college.
“For those who have two or three children in college, it can be really straining on them.”