It now costs more than a €1,000 a month to rent a place to live in seven counties.
Cork, Dublin, Galway, Kildare, Louth, Meath and Wicklow all have average rental costs that top the €1,000-a-month mark.
Limerick falls just under this threshold, according to the latest rent index from the Residential Tenancies Board (RTB).
The index shows that rents nationally rose by another 7pc as the accommodation crisis worsened.
Two more areas have been designated rent pressure zones - the Carlow and Macroom electoral areas.
The average cost of renting a home across the State is now €1,202 a month, up €79 over the last year.
Rises in Dublin are much greater, with an increase of €114 in the monthly cost of renting to €1,713 in the last year. This is a rise of 7.1pc in the last year.
The index shows huge variations in rent costs across the country.
In Stillorgan, in south Dublin, the cost has measured at €2,328 a month.
On the other side of the State, it costs €489 a month to rent in Lifford-Stranorlar, Co Donegal.
Rental cost surges have been so great in the last few years that the index is now 21pc higher nationally than it was during the peak of the housing boom in 2007.
The index is based on almost 20,000 new tenancies registered with the RTB between April and June.
The largest rises have been seen in renewed tenancies rather than tenancies registered for the first time.
Limerick falls just under this €1,000 threshold with a standardised average rent of €991.
Outside Dublin, the average rent is now €903.
Director of the RTB Rosalind Carroll said: "While the pace of rental growth has slowed since our last quarterly report, the continued growth levels over consecutive quarters is not sustainable."
Reacting to the figures, last night Housing Minister Eoghan Murphy said: "In our key employment areas, but particularly in Dublin, rents have reached unsustainable levels."