Payoff Balance Calculator: Estimate Your Loan Balance

A payoff balance calculator estimates the amount of principal remaining on a fixed-rate loan after a chosen number of monthly payments. Enter the original loan amount, APR, term, and payments already made to see the estimated balance and the amount paid toward principal; it does not include a lender’s payoff fees or other account-specific charges.

Formula

The balance after a set of level monthly payments is the original principal grown by monthly interest, minus the accumulated value of those payments:

B = P(1 + r)^k − M[((1 + r)^k − 1) / r]

• B is the estimated balance in dollars after the selected payments.
• P is the original loan principal in dollars.
• r is the monthly interest rate, calculated as APR ÷ 1,200.
• k is the number of monthly payments made.
• M is the scheduled monthly payment in dollars. It is calculated from the loan amount, APR, and full term, then rounded to cents.

The payment used here is M = round(P × r / [1 − (1 + r)⁻ⁿ], 2), where n is the term in months, or years × 12. The second displayed result, principal repaid, is simply P − B. It is not the same as total payments made: early payments include interest as well as principal.

Worked Example

Using the calculator’s defaults: a $20,000 loan, 8% APR, a five-year term, and 12 payments made.

1. Convert the term to months: n = 5 × 12 = 60.
2. Find the monthly rate: r = 8 ÷ 1,200 = 0.0066667.
3. Calculate the scheduled payment: M = round[20,000 × 0.0066667 ÷ (1 − (1.0066667)⁻⁶⁰), 2] = $405.53.
4. Apply the balance formula after 12 payments: B = 20,000(1.0066667)¹² − 405.53 × [(1.0066667¹² − 1) ÷ 0.0066667] = $16,384.67, rounded to cents.
5. Calculate principal repaid: $20,000 − $16,384.67 = $3,615.33.

The example’s $4,866.36 in scheduled payments (12 × $405.53) is greater than the principal reduction because part of each payment covers interest. The figures are estimates based on the stated assumptions and cent-rounded monthly payment.

Assumptions

• The interest rate is fixed for the full term.
• Payments are equal, made monthly at the end of each monthly period.
• Interest compounds monthly at APR ÷ 12.
• The model excludes fees, taxes, insurance, PMI, escrow, late charges, and extra or missed payments.

When to Use a Payoff Balance Estimate

This calculation is useful when you want a rough view of how a loan balance changes over time, or want to check the principal remaining after a certain number of scheduled payments. It can also help explain an amortization schedule: each payment is split between interest and principal, and the split shifts as the balance declines.

Enter the original amount borrowed, not the sum of payments you expect to make. Use the annual percentage rate shown in the loan paperwork and the original term. “Payments made” means completed monthly payments, not the number of months since borrowing if a payment was skipped, delayed, or applied differently. The input allows up to 600 payments; it should not exceed the number of scheduled payments in the loan term if you want a meaningful result.

To read the result, compare the estimated balance with the amount originally borrowed. The principal-repaid figure shows how much of that original amount has been reduced under the model. It does not show total interest paid, nor is it a quote for closing or settling the account. A lender’s payoff figure may differ because it can use the exact payment dates, accrued interest through a specific date, and applicable account charges or credits.

Common Sources of Differences

• Different payment dates: This calculator treats every period as one month. A lender may calculate interest using actual dates or a different day-count convention.
• Variable APR: If the rate changed, one fixed-rate calculation cannot reproduce the actual payment history. A changing rate requires the rate and payment for each period.
• Extra, missed, or late payments: These alter the schedule. An extra principal payment generally changes the balance, while a missed payment may cause interest or charges to accrue differently.
• Rounding: Payments are rounded to cents, and a lender may handle rounding at each period or adjust the final payment. Small differences can accumulate.
• Loan type: Interest-only periods, balloon payments, deferred payments, and irregular payment schedules do not follow the standard level-payment formula throughout.

A common misconception is that the balance equals the original principal minus monthly payment multiplied by the number of payments. That subtraction ignores interest. For example, in the worked example, 12 payments total $4,866.36, but the principal falls by only $3,615.33 because the remaining portion covers interest under the model.

Limits and Alternatives

For a closer estimate of a real account, use a transaction-by-transaction amortization schedule with the actual payment dates, rate changes, and extra principal amounts. To request an exact amount for a particular date, use the payoff figure supplied by the loan servicer; this calculator cannot retrieve account data or determine charges that depend on the contract.

The formula assumes the scheduled payment fully amortizes the principal over the stated term. The APR input must be from 0.01% to 100%, and the loan amount must be positive. If the loan has a promotional rate, fees financed into the balance, or a final payment different from the regular amount, the estimate may not match its schedule. This is estimate arithmetic for education, not financial advice. The result is an estimate, and the lender’s disclosure gives the exact figures.

Frequently Asked Questions

How do I calculate my loan balance after a payment?
Use the balance formula with the original principal, monthly rate, scheduled payment, and number of completed payments. This calculator derives the scheduled payment from the APR and term.

Is the estimated balance the same as a payoff amount?
No. A payoff amount is calculated for a specific date and may include accrued interest and account-specific charges or credits. Ask the servicer for that figure.

Why is my balance not dropping by the full payment?
Each scheduled payment first covers interest due for the period under the loan’s rules. The remainder reduces principal, so the principal reduction is normally less than the payment amount.

Can I use this calculator if I made extra payments?
Not accurately with this basic calculator. It assumes equal scheduled payments and no extra payments. An amortization schedule that includes the amount and timing of each extra payment is needed.

What if my APR changed during the loan?
A single APR cannot represent a variable-rate history. Calculate each period using the rate and payment that applied then, or consult the servicer’s current account balance.

Related

• Beginning Balance: How to Calculate It
• How Minimum Balance Is Calculated
• Opening Balance: How to Calculate It

in p | Loan amount | $ | 20000 | 1 | 100000000
in apr | Interest rate (APR) | % | 8 | 0.01 | 100
in yrs | Loan term | years | 5 | 0.0833 | 50
in k | Payments made | - | 12 | 0 | 600
out bal | Estimated balance | $ | p * (1 + apr / 1200) ^ k - round(p * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)), 2) * ((1 + apr / 1200) ^ k - 1) / (apr / 1200) | 2
out paid | Principal repaid | $ | p - bal | 2