The number of homeowners in the Republic falling behind in their repayments has jumped from 49,609 at the end of March to 55,763 at the end of June.
A Central Bank report shows that more than 7% of all mortgages in the Republic are in arrears for more than 90 days.
There has also been a rise in the number of mortgages that have been "restructured" to help homeowners meet their repayments, up almost 7,000 from March to 69,837 just three months later.
The Central Bank said more than half of these - 39,395 - were not in arrears and mortgage holders were making the repayments as agreed under the new arrangement.
The report by the Central Bank also reveals:
At the end of June, financial institutions had more than 800 repossessed properties in their control.
Figures from the Northern Ireland Court Service earlier this month showed that court actions by lenders seeking to repossess homes in the province have gone up by at least 60% since just before the credit crunch.
There were 939 actions started by banks and building societies against customers who were in arrears between April and June this year, compared to 584 during the same period in 2007.