The divergence between asking prices and final sold prices is among the reasons for poor liquidity in the existing homes market, according to a report.
The study, which was carried out by property listings website MyHome.ie in association with Bank of Ireland, said the issue is contributing to "an unclear picture for both would-be buyers and vendors."
The report said that one-in-seven of all housing transactions are settled for at least 20% over the original asking price, with two-in-five settled at 10% or more above the asking price.
The study said in too many cases "asking prices are not an optimal guide for homebuyers, adding to the time and effort required to buy or sell a home."
The report said the issue is among the reasons for poor liquidity in the existing homes market, "with the average property being sold once every 50 years."
It said the rate at which existing homeowners, with mortgage debt, move home is now less than half the UK level.
The research concluded that "Ireland's opaque process of buying and selling homes is contributing to current poor levels of housing liquidity."
It states that "a lack of transparency in bidding, along with an emerging divergence between the asking price and final sold price of properties, are amongst a range of inter-related issues that have led to the liquidity in the Irish housing market falling behind European countries, the UK and US."
It recommends that estate agents continue to adopt and encourage the use of emerging online transparent bidding platforms, "as they can provide greater trust and confidence in the housing market."
According to the report, there were 61,000 residential property market transactions in Ireland in 2024, which it said is equivalent to 2.8% of the housing stock.
"This turnover rate was well below the UK’s turnover rate of 3.6%, itself depressed by rising interest rates and well down from the 4.2% rate on average it experienced through 2013-2022."
The study said liquidity in the Irish housing market has "lagged behind the UK in every year since the global financial crisis, seeing turnover rates even below those of Northern Ireland, which saw a similar house price collapse to ours."
It found the issue is most pronounced among existing homeowners with mortgage debt looking to move home.
"Just 9,000 mortgages were drawn down by movers in 2024; this represents just 0.4% of our housing stock, which is less than half the UK rate of 0.9%."
The Chief Economist of Bank of Ireland said the fact that Irish housing supply has failed to keep pace with buoyant demand and many of the challenges are well understood.
Conall MacCoille, the author of the report, said that "perhaps less appreciated is the process of buying and selling existing homes is also impeded by an opaque bidding process and the emerging discrepancy between asking prices and final sold prices."
"These combined factors have led to poor rates of liquidity, consistently below other European countries, the United Kingdom and the United States."
Mr MacCoille said the introduction of the Property Price Register has "brought welcome transparency to the Irish housing market but there is scope to go further."
"Estate agents are already required to disclose legitimate bids to the PRSA. Allowing prospective buyers to see these bids, via new technology platforms, can only help the functioning of the Irish housing market," he added.
The Managing Director of MyHome said a fully transparent bidding process "may improve market functionality and, by extension, help to improve housing liquidity."
Joanne Geary said at present close to half of residential transactions are visible on platforms that feature online bidding or auctions, including MyHome offers
"A key advantage of these platforms is that they provide buyers with transparent information about the bidding history of the properties they are interested in, as well as giving the buyer the digital means to view and place an offer at any time."
The report also noted that a recent survey from the Competition and Consumer Protection Commission noted that just 16% of buyers felt the housing market is transparent.
