Rents in Dublin are now on average €1,600 per month , a €130 increase in the last 12 months.
The new data separates new and existing tenancies for the first time and shows a massive difference between rates of increases for existing tenants and those looking to rent for the first time.
The figures, produced in conjunction with the ESRI, are based on over 18,000 new tenancies registered with the Residential Tenancy Board.
It shows that between April and June the average national rent increased from up from €1,017 last year to €1,094 in 2018.
The RTB is seeking powers for a rent registry which would allow for greater transparency for new tenancies.
Director Rosalind Caroll said many people do not know the rules surround rent pressure zones and think that the 4% increase cap only applies to existing tenancies, but the landlord is obliged to tell new tenants what the rent was before.
She went on to say, "transparency is an issue."
She told RTÉ's Morning Ireland, “So what we’re doing at the moment is working with the Minister and the Department officials to try and get legislation through that will bring that transparency - a rent register.
“A rent register is prohibited, until that law is changed we can’t do anything.
“We’re also going to get new powers that, instead of waiting for tenants to come to us, will allow us to proactively go out, investigate and sanction, where we see any contraventions in the law.”