Almost 700,000 people now live in rented accommodation.
The latest figures from the Private Residential Tenancies Board show that 10,000 people a month are moving into rental properties.
According to the Irish independent, the total is just under 700,000 - compared to 455,000 in December 2013, and marking an increase of 55,000 since last December.
The paper reports that mortgage approvals have stalled, with around 2,000 issued in March 2015.
A housing supply shortage and stricter mortgage rules are being blamed for the increase.
At the weekend, a new analysis of the cost of renting across the country showed big increases in Dublin, Cork and Galway over the past five years - with drops everywhere else.
The report found that only in Dublin, Galway and Cork is it more expensive to rent than it was five years ago.
Earlier this month it was reported that temporary rent controls could be introduced soon, as part of efforts to help thousands of families who have been hit with repeated increases.