Rents are now 2% lower than they were in January, according to property website Daft's latest rental report.
It is the first fall in rent in four years and Daft says it signals a move from the boom period of ever-growing rents to a calmer period of more normal growth.
The average monthly rent now stands at €1,369, showing a 2% fall since the start of the year. This is largely down to an increase in the number of properties available to rent.
12,000 properties are now available, double the properties that were available in May last year.
There are some regional variations - rents in west Dublin have gone up slightly, while rents in Limerick city and Dublin city centre have fallen by 3%.
Daft says that rents will continue to fall, which is good news for renters.
It adds that landlords need not be concerned if their investment is long-term, the quality of their property is high and the property is professionally managed.
