EBS has become the fourth lender to increase mortgage rates in the last week.
It announced late on Friday it was hiking its standard variable rate by 0.6 per cent, following in the footsteps of other mortgage companies, KBC, Permanent TSB and Ulster Bank who have all increased mortgages in the last week.
EBS customers with a €300,000 mortgage will see an annual increase in their mortgage of €1,254.96 - €34.86 a month for every €100,000 owed.
Permanent TSB earlier confirmed it was putting its fixed rates up by 2% and 3%, a move that was described as "shocking" by mortgage brokers.
The increase is designed to persuade those on fixed mortgages to switch to the standard variable rate, which it increased by one per cent a week ago.
The two-year rate is rising from 5.25% to 7.25%, the five-year goes from 5.75% to 8.75%, while the seven- and ten-year rates both rise from 6.1% to 9.1%. The new rates are effective from the start February 11.
It is giving customers who are coming off the fixed rates 20 days to consider their options.
Permanent TSB did not announce the changes but responded to press enquiries after speculation filtered through to mortgage brokers about the hike.
It is one of the largest mortgage firms in Ireland alongside Bank of Ireland and AIB but it says only "a small portion" of its 200,000 customer base will be affected.
About 80,000 of its customers are on the standard variable rate. They are facing significant increases in their monthly payments from next month when the banks increases the interest rate by a further one per cent.
It will add more than €60 a month on mortgages worth €100,000 and €180 a month on mortgages worth €300,000.
The bank says all fixed rates will remain under review as the cost to the bank of borrowing money continues to fluctuate.
Brokers' group, the Professional Brokers Insurance Association, described the rises as 'shocking' and much higher than anticipated.
Irish Nationwide halts new mortgage lending
The increase is part of a growing upward trend as banks struggle to meet losses from their tracker mortgages, which are contractually linked to the European Central Bank rate, currently set at one per cent.
Last week the Ulster Bank put its standard variable rate up 0.5% while KBC put its mortgage interest rate by 0.7% for new and existing customers.
EBS is expected to increase its variable rate by 0.6 per cent, a move that will add €34 to the average monthly repayment for each €100,000 owed.
On February 11, the Irish Nationwide Building Society announced it was stopping new mortgage lending with immediate effect.
The move follows the High Court order earlier this week, which allowed the State to start the process of selling the deposits of Anglo Irish and Irish Nationwide to another institution.
In a letter to mortgage brokers, the society said the court order - which facilitates the restructuring of the institution under the EU/IMF programme - also required it to limit increases in mortgage lending to contractually committed amounts and amounts arising from the restructuring of existing mortgages.
Irish Nationwide said this limited it to honouring offers already made, provided they were completed within a stipulated timeframe.