The latest figures paid by people renting houses and apartments across the country show the highest increase in rental costs is in Leitrim.
The figures from the Residential Tenancies Board show rents in Dublin are up 4.4 percent year-on-year, while outside the capital it's increased even more.
This latest report is based on actual rents paid of 13,884 private tenancies registered with the RTB for April to June of this year.
Rental costs in Leitrim are said to have jumped by 17.3 % since March, bringing the average cost now to €704 euro.
In Longford, the year-on-year change is up over 15% - to bring the average rent to €755- but the rise from quarter to quarter was just under 4%.
Rental costs in other counties in the Shannonside Northern Sound region have remained more stable.
Monaghan and Roscommon both saw increases of almost 6% since the first quarter of the year, while Cavan showed an average increase of 3%.
The cost of rent in the region ranges from €704 euro in Leitrim to €761 for properties in Cavan.