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Quick answer
- Overpayments reduce the mortgage balance faster.
- Reducing the balance can reduce future interest.
- Fixed-rate mortgages may limit overpayments or charge break fees.
- Overpayments should be compared with emergency savings and other debts.
On this page
How overpayments work
A mortgage overpayment is any payment above the normal required repayment. This might be a regular extra monthly payment or a once-off lump sum. The aim is to reduce the outstanding balance faster.
Example overpayment scenarios
Example based on a €300,000 mortgage over 30 years at 4.00%, using the normal repayment of about €1,432 per month.
| Overpayment | Approx. time saved | Approx. interest saved |
|---|---|---|
| €100 extra per month | 3 years 6 months | €28,747 |
| €200 extra per month | 6 years 2 months | €50,412 |
| €10,000 lump sum | 1 year 10 months | €21,972 |
| €100 monthly + €10,000 lump sum | 5 years | €46,716 |
When overpayments may not be best
Overpaying may not be the best first move if you have expensive short-term debt, no emergency fund, or a fixed-rate mortgage with overpayment restrictions. Some borrowers may prefer to keep cash available for repairs, children, business risk or moving costs.
Check your lender terms first
Variable-rate borrowers may have more flexibility, while fixed-rate borrowers may face limits or early repayment charges. Before making a large overpayment, ask the lender how it will be applied and whether it reduces the term, repayment amount, or both.
Frequently asked questions
Can I overpay my mortgage in Ireland?
Often yes, but it depends on your mortgage terms. Fixed-rate mortgages may have limits or break fees.
Is it better to reduce term or monthly repayment?
Reducing the term usually saves more interest, while reducing the payment improves monthly cash flow.
Are mortgage overpayments taxable?
The act of overpaying a home mortgage is not usually a tax event for a personal borrower, but financial advice may be useful.
Should I overpay or save?
Compare the mortgage rate, savings rate, emergency fund needs and other debts.
Do overpayments always save interest?
They generally can if they reduce the loan balance and no fees outweigh the benefit.
Is this guide tax advice?
No. It is general information for planning. Use official guidance or a tax adviser for your own situation.
Can I use the calculator for filing?
Use it as an estimate only. Complex activity such as DeFi, staking, mining, business trading, or many swaps may need specialist software or advice.
Sources & references
Key takeaways
- Overpayments can reduce both term and interest.
- Fixed-rate terms may limit overpayments.
- Emergency savings and expensive debts should be considered first.
- Ask the lender how an overpayment will be applied.