How to use the remaining mortgage balance calculator
- Enter the original loan amount, the interest rate and the loan term in years.
- Enter the payments made so far in months. Count the payments already made, not the next one due.
- If you paid extra principal every month, open More options and enter it.
- Read the remaining balance, the principal and interest paid so far and the number of payments left.
Formula
Monthly payment = P x i x (1 + i)^n / ((1 + i)^n - 1), with i = rate / 12 and n = months
Each month: interest = balance x i, and principal = payment - interest
Balance after k payments = P x ((1 + i)^n - (1 + i)^k) / ((1 + i)^n - 1)
The calculator builds the schedule month by month with the payment rounded to the cent and each month's interest rounded to the cent, the way a lender does. The closed-form balance is shown as a check and can differ by a few cents.
$300,000 at 6.5% for 30 years, after 60 payments
The payment is $1,896.20. After 60 payments the schedule leaves $280,833.26, so $19,166.74 of principal has been repaid and $94,605.26 has gone to interest. The closed-form formula gives $280,832.93, a difference of 33 cents from rounding the interest each month.
The first five years pay down only about 6.4% of the loan, because early payments are mostly interest. With an extra $200 a month for the same 60 months the balance would be $266,698.50 and the loan would finish after 277 payments instead of 360.
Why the balance falls slowly at first
Interest is charged on the balance, which is largest at the start. A level payment therefore covers mostly interest early and mostly principal later. That is why paying a loan down a little early saves so much interest, and why the balance after five years of a 30-year loan is still close to the original amount.
Balance versus payoff amount
Your lender's payoff quote can differ from this balance. It includes interest accrued since your last payment and may include fees, and a loan that has been modified, recast or paid with unusual amounts will not match a standard schedule. Escrow for taxes and insurance is separate from the loan balance.
To see how extra payments change the finish date use the Mortgage Payoff Calculator, for the full list of payments use the Amortization Schedule Calculator, and to estimate cash from a sale use the Home Sale Proceeds Calculator.
Assumptions and limits
- The loan has a fixed rate and level monthly payments with no balloon.
- Payments were made on schedule, and extra principal, if any, was the same every month.
- Interest is calculated monthly at one twelfth of the yearly rate.
- Nothing is uploaded. Calculations run in your browser.
Frequently asked questions
How do I find how many payments I have made?
Count the months from your first payment to your latest one. Your loan statement also shows the principal balance directly, which is the best check on this estimate.
Why does the balance differ from my statement?
Statements reflect your real payments and any changes to the loan. Differences can come from extra payments, missed payments, a rate change or rounding. Treat this page as an estimate and rely on your lender's figure.
Does this work for a car loan or student loan?
Yes for any fixed-rate loan with level monthly payments. Enter the amount, rate and term, and the number of payments made.
What happens at 0% interest?
The payment is the loan divided by the number of months, rounded to the cent, and no interest is paid. The last payment adjusts by a few cents so the balance ends at zero.