Loans for house prices were down 2.2% in the second quarter, following a quarterly decline of 0.7% in the first quarter.
This is despite house prices picking up across the country, particularly in the capital.
Estate agents have estimated though that anything up to two-thirds of transactions may now be cash transactions.
The outstanding amount of loans for house purchases on-balance sheet stood at €83.6bn at the end of June. A further €41bn of securitised mortgages, which continue to be serviced by resident credit institutions, was also outstanding.
Half of all outstanding loans for house purchases are on tracker mortgages.