Permanent TSB is to raise its variable interest rate by 0.5% from Tuesday, August 3, the bank announced today.
The new Standard Variable Rate for the bank's customers after the increase will be 4.19%, up from the previous 3.69%.
The banks' chief executive David Guinane said that the bank regretted having to make this decision but that it "reflected the continuing high costs of funds for the bank".
The changes will affect approximately 80,000 customers or 38% of the bank’s residential mortgage customers. It will have no impact on customers with fixed or tracker mortgage products.
The hike will mean a further €100 per month - or €1,200 per year - on a €300,000 mortgage.
PTSB said its average mortgage for customers with SVR residential mortgages is €66,532. Some 60% of Permanent TSB's SVR customers have a mortgage of less than €60,000.
The impact of this rate increase on the average mortgage (€66,352) will be about €17 per month.