Mortgage Top Up Calculator Ireland
Use this mortgage top up calculator for Ireland to see what happens if you borrow extra against your home, for example for a renovation or extension. Enter your current balance, rate and remaining term, the top-up amount, and the new rate and term, and compare the new monthly payment with your current one.
Calculator
How to use this calculator
- Enter your current mortgage balance, interest rate and remaining term to get your current payment.
- Enter the top-up amount you want to borrow, plus the new rate and term the lender offers on the combined loan.
- Click Calculate to compare the new payment with the current one and see the total interest over the new term.
Worked example: a €180,000 balance at 4.2% with 20 years left costs about €1,110 a month. Adding a €30,000 top-up and moving to 4% over 25 years gives a €210,000 loan at about €1,108 a month — almost the same payment, but paid for five years longer, so the total interest is higher.
Frequently Asked Questions
How does a mortgage top-up work in Ireland?
A top-up increases your existing mortgage by an extra amount, secured on your home. The lender reassesses affordability and the property value before approving it.
Is a top-up cheaper than a personal loan?
The rate is usually lower because the loan is secured on your home, but it is repaid over a much longer term, so the total interest can be higher. Compare both on total cost, not just the monthly payment.
Do I need a valuation for a top-up?
Usually yes. The lender needs to confirm the property value supports the larger loan, and there may be legal and valuation fees.
Can I top up at any time?
Most lenders require a period of good repayment history first, and the top-up is subject to a fresh affordability check and the Central Bank lending rules.