Property website daft.ie has reported that rents fell by almost 12% in the past year.
The average rent nationally now stands at €885, down from €1,000 in the same period last year.
The report says 10,000 new properties come to the market every month, meaning that the total number of properties available to rent in the country at any one time is 20,000.
Read the report in full
South county Dublin was the area most affected by falling rents, with an average 15% decline over last year to an average rent of €1,386 a month.
Cork and Limerick saw a fall of 10%, while rents in Galway and Waterford fell by 6% and 4% respectively. The fall in rents outside major cities was 8%.
The daft.ie report predicts that average rents could fall by another 20% this year.