The national average rent has had its lowest growth rate since 2012.
The Residential Tenancies Board Index shows average rent across the country is over 1,250 euro per month.
The index shows it costs €300 more to rent a one-bedroom apartment in Dublin than a three bed property outside the county.
The national average is over €1,250 per month, while in Dublin it is more than €1,750.
This is the first time that standardised average rents in Limerick have exceeded €1,000 euro per month.
Meanwhile the fastest growing area for cost was seen in County Waterford.
The county with the largest year-on-year decline was Sligo.
Stillorgan in Co. Dublin had the highest rates at €2,319 per month.
Carndonagh in County Donegal had the lowest in the country at €498 euro per month.