About this Mortgage Payoff
Mortgages are front-loaded with interest. By making extra principal payments, you attack the balance directly, reducing the interest charged in every subsequent month. This creates a snowball effect that can shave years off your loan.
How to use this calculator
- Enter your Current Loan Balance.
- Enter your Interest Rate and remaining Term.
- Add an Extra Monthly Payment to see the impact.
Accuracy and testing
Review formula sources, default test cases, assumptions, unit handling, rounding rules, and changelog for this calculator.
How this calculator works
Inputs explained
Current Balance
The amount you still owe (principal only), not the original loan amount.
Remaining Term
How many years are left on your contract. If you are 5 years into a 30-year mortgage, enter 25.
Extra Monthly Payment
Additional money paid over and above your required monthly payment, designated for principal.
Understanding your results
Example scenarios
Small Extra Payment
$200k loan at 6% for 30 years. Payment $1,200. Adding just $100/mo saves ~$47,000 in interest and pays off 4.5 years early.
Bi-Weekly Strategy
Paying half your monthly payment every 2 weeks results in 13 full payments per year (one extra month). This typically shaves 4-6 years off a 30-year loan.
Key Features
- Time Saved Calculation
- Interest Savings
- Extra Payment Logic
Things to Keep in Mind
Assumes the extra payment amount stays constant for the entire remaining term. Does not account for lump sum payments.
Tips & Best Practices
- Make sure your lender applies extra payments to the *principal*, not to future interest.
- Ensure there are no 'prepayment penalties' on your mortgage (most modern loans do not have them).
- Compare the interest saved vs investing that extra money. If your rate is low (e.g. 3%), investing might yield higher returns.
Glossary of Terms
- Principal
- The actual money borrowed that you are repaying.
- Amortization
- The schedule of payments that pays off a loan over time.