Average rents rose by 11.5% in the year to March, according to the latest Daft.ie rental report covering the first three months of the year.
The increase represents the eighth consecutive quarter in which annual rent rises have been above 10% and a new all-time high has been set.
The study shows average monthly rents across the country reached €1,261 during the first three months of the year.
This is €232 per month higher than the pre-crisis peak in 2008, meaning that ten years later, tenants are paying almost €2,800 more annually to rent a property.
Dublin has seen the sharpest increases, with average rents rising by 12.8% over the past year to nearly €1,900.
Rents in the capital are now 30%, or €430, higher per month than in 2008.
Prices are also continuing to rise rapidly in other cities.
In Limerick, rents were 17.1% higher than a year ago, while in Waterford, the increase was 14.6%.
Galway saw its rents increase by 13.6% in the same period, while in Cork, rents rose by 9.3%.
Outside the five main cities, rents rose by an average of 10.1%.
At the other end of the spectrum, with a 0.3% rise to €594, Donegal saw the lowest rate of increase in rents of any county over the past year.
The country's cheapest rents are to be found in Leitrim, with average prices for the county coming in at €545 during the first quarter.
The Daft report also states there were 3,086 properties available to rent nationwide in April, which is the lowest number ever recorded for this time of year since the series started in 2006.
The figure marks a 17% decrease on the same date a year previously.
In Dublin, there were just 1,265 homes available to rent, one third below the average over the last five years and just one quarter of the average in the period 2008-2013.
Commenting on the report, TCD Economist and report author Ronan Lyons said: "Rents have now been rising almost three times as long as they fell in the crash and the increases show no signs of moderating.
"With the exception of Donegal - where Brexit is having a clear effect on the local market - the problem is countrywide, although it is certainly most acute in Dublin.
"It is clear that, for those who have to look for a new home in the open market, rental inflation remains well above any reasonable measure of health. But as ever, rents are only the symptom.
"The cause remains a chronic and worsening lack of rental supply," he added.