New Central Bank research shows that a down payment for a first time buyer in Dublin last year hit €50,000 last year after increasing steadily since 2012.
The research said that a down payment for a first time buyer outside of Dublin reached €25,000, well below earlier peaks.
The Central Bank said that a typical Irish home buyer had a 20% deposit last year, while first time buyers had a deposit of closer to 15%.
Its research also shows that about 20% of Irish home buyers reported receiving an inheritance before they bought a house. This tends to make up about half of the deposit amount.
The Central Bank's economic letter - authored by Jane Kelly and Reamonn Lydon - show that the median level of down payments here is at the lower end of the range compared to many other countries.
Savings and inheritance patterns, however, are "remarkably" similar across most countries, the Central Bank noted.
The Central Bank has said it will act if there is a "rapid increase in house prices" after announcing changes to mortgage lending rules for first-time buyers.
Last November, the Central Bank said it was removing the €220,000 cap on mortgage lending for first-time buyers who have a deposit of 10%. The move came into effect in January of this year.
This was a shift from the previous requirement - introduced in February 2015 - which put the ceiling at 90% for loans up to €220,000 but at 80% for the rest of the mortgage above €220,000.
The 20% minimum deposit requirement still applies to second and subsequent buyers.
Central Bank Governor Philip Lane said he was changing the mortgage rules in response to rising house prices and higher incomes.