Irish lenders have so far paid out €647m in redress and compensation to customers affected by the tracker mortgage scandal.
A Central Bank examination of two million mortgages has found a further 1,400 homeowners were affected.
This afternoon, the regulator said the number of customers known to have been either denied a tracker rate or charged the wrong rate of interest stood at 39,800 at the end of December.
In some cases this led to families losing their homes.
In what is expected to be its second-last update on the scandal the regulator said 97% of affected customers had received offers of redress and compensation by the end of 2018.
Derville Rowland, Director General for Financial Conduct at the Central Bank, said the regulator will continue to put pressure on the banks until all affected customers have been identified.
“That has been our demand of them right throughout this examination,” she said. “And it certainly is our continuing demand in this work and in all of their dealings with their customers.
“They must have a customer-centric view and be able to demonstrate that by the outcomes they deliver for their customers.
“We will be judging them on that in this examination and in all of their obligations.”
The €647m paid is an increase of €67m since the last update at the end of August last year.
Ms Rowland said more customers may yet be identified before the Central Bank investigation is complete.
She said the investigation has highlighted the “unacceptable damage that misconduct can cause to consumers up to and including the loss of their homes and properties.”
On Newstalk Breakfast this morning, Brendan Burgess, founder of Ask About Money, said the increase in affected customers is not surprising.
“One would expect an increase like this in any major operation in a banking environment so I am not surprised by it,” he said.
“As with any company or industry, some companies are more efficient than others and AIB and PTSB seemed to get their hands around the system much more quickly than some of the others.”
The Central Bank said its final report into the scandal is expected to be published in the coming months.
