The number of homes selling for more than a million euro across the country is continuing to rise.
MyHome.ie says 826 properties sold for above €1 million last year - up 25% on 2016.
House prices are continuing to rise in general, but the rate of increase has slowed in Dublin.
The report from shows the cost of buying a newly-listed home in the capital is up 3.3% in the first three months of the year - compared to 4.8% nationally.
Dublin prices are up 8.2% over the past year, while nationally the increase is 9.5%.
The median asking price for new sales in Dublin is €345,000, while the price outside Dublin is €210,000.
The report's author - chief economist at Davy, Conall MacCoille - suggested housing supply is starting to improve slightly.
He told Breakfast Business: "Things are getting a little bit better, but still well behind demand.
"If we look at the number of properties listed for sale on the website, it's broadly flat on the year. But actually in Dublin the number of properties listed for sale are up 20%."
He added: "If you look at the number of new developments listed for sale, again they're up 24%. So finally, after years where effectively very few homes were being built, you're beginning to see the new supply of new homes."