Mortgage Overpayment Calculator
See how much interest and time you save by paying extra on your mortgage each month.
…
How to do it
- 1Fill in the boxes
Type your numbers or pick the options you need.
- 2See the result
The answer updates right away as you change a value.
- 3Use it
Copy the result or note it down. Nothing is sent anywhere.
About this tool
Enter your mortgage balance, rate, remaining term and an extra monthly payment. The calculator shows the normal payment, total interest with and without the extra, the months saved and the new term.
How overpayments help
Extra payments go straight to the balance, so you pay less interest each following month. The effect grows over time because interest compounds on the lower balance. Even a small monthly overpayment can take years off a long loan.
Example
On a $250,000 balance at 5 percent over 25 years, an extra $200 a month saves about $41,000 in interest and shortens the loan by around 4 years.
Check first
Some loans charge for overpaying above an allowance, such as 10 percent a year. Compare with other uses of money, such as clearing high-interest debt or saving.
Frequently asked questions
Is there a penalty?
Some mortgages, especially fixed deals in the UK, limit penalty-free overpayments to 10 percent a year. Check your terms.
Is it better to reduce the term or the payment?
Keeping the payment and cutting the term saves the most interest.
Should I overpay or invest?
If your mortgage rate is higher than the return you expect after tax and risk, overpaying is a guaranteed saving.
Does it work for US and UK loans?
Yes. The maths is the same for any amortizing loan paid monthly.