Personal Loan Payoff Calculator in Excel

A personal loan payoff calculator in Excel estimates your monthly payment, total interest, and remaining balance from the loan amount, APR, term, and payment schedule. Enter the loan details and any extra payments to see how the payoff timeline changes; the standard fixed-payment calculation below provides a baseline, while an Excel sheet can model additional payments month by month.

Formula

This calculator uses the standard fixed-payment loan formula. Let P be the starting principal in dollars, APR the annual percentage rate entered as a percentage, r the monthly rate, and n the number of monthly payments. The monthly rate is r = APR / 1200, and the number of payments is n = years × 12.

Monthly payment = P × r / [1 − (1 + r)⁻ⁿ]. Total interest = monthly payment × n − P. The displayed outputs are rounded to cents. This compact calculator uses the unrounded payment in the total-interest expression; a real amortization schedule usually rounds each scheduled payment and interest posting to cents, so its final figures can differ slightly.

The formula assumes the same payment is made once each month and the rate stays fixed. It estimates the scheduled payoff; it does not separately model extra payments, changing rates, fees, or a lender’s particular posting rules.

Worked Example

Using the calculator’s default inputs: principal P = $20,000, APR = 8%, and term = 5 years:

1. Convert APR to a monthly rate: r = 8 / 1200 = 0.0066667, or about 0.66667% per month.
2. Convert the term to payments: n = 5 × 12 = 60.
3. Substitute into the payment formula: $20,000 × 0.0066667 / [1 − (1.0066667)⁻⁶⁰] ≈ $405.53 per month.
4. Calculate estimated interest using the displayed payment: $405.53 × 60 − $20,000 = $4,331.80.

These figures are estimates under the stated assumptions. A lender’s actual payment schedule may vary because of rounding conventions, payment dates, or loan terms not represented here.

Assumptions

• The rate is fixed for the full term.
• Payments are equal monthly payments, made at the end of each monthly period.
• Interest compounds monthly using APR divided by 12.
• Fees, taxes, insurance, and other charges are not included. Extra payments and their timing are not included in these two outputs.

How to Build a Payoff Schedule in Excel

To track payoff month by month in Excel, create columns for payment number, starting balance, scheduled payment, extra payment, interest, principal paid, and ending balance. Put the loan amount, APR, and term in separate input cells. If those are in B1, B2, and B3, respectively, a standard payment formula is =-PMT(B2/12,B3*12,B1). The minus sign makes the payment appear as a positive number under Excel’s cash-flow sign convention.

For the first schedule row, calculate monthly interest as starting balance multiplied by APR divided by 12. Principal paid is payment minus interest, and ending balance is starting balance minus principal paid. For later rows, use the prior row’s ending balance as the new starting balance. Add an extra-payment input to the principal reduction, but do not let total principal paid exceed the current balance. Copy the formulas down until the balance reaches zero. The final payment should be capped at the amount actually owed, including that period’s interest; otherwise a spreadsheet may show a negative remaining balance.

Excel’s PMT function returns a constant scheduled payment, but it does not itself produce the monthly balance table or account for extra payments. A schedule is useful when you want to change the payment amount or enter irregular additional amounts. Confirm the lender’s rules on how extra payments are applied and whether the payment date affects accrued interest; those details are outside this simple calculation.

How to Read the Results and When to Use Them

The monthly payment is the modeled amount required to repay principal and interest over the entered term under the fixed-rate assumptions. Total interest is the estimated borrowing cost over that schedule, not the total of all payments. Adding principal to interest gives the estimated total repaid, before any excluded charges.

Use the baseline to understand the arithmetic in a loan disclosure or to compare different hypothetical amounts and terms while holding other inputs constant. Treat APR, payment amount, fees, and other quoted terms as inputs to verify with the lender; do not assume an example rate applies to any actual offer. The calculation does not establish approval, affordability, or the exact amount a lender will collect.

Common Excel Errors and Limits

• Entering APR incorrectly: If the APR cell contains 8 for 8%, divide by 12 and by 100 in the formula, as in B2/1200. If the cell is formatted as a percentage and contains 8%, the appropriate monthly-rate expression is B2/12. Mixing the conventions changes the result substantially.
• Mixing years and months: PMT needs the total number of payment periods. Convert a term in years to months by multiplying by 12; a term already in months should not be multiplied again.
• Rounding too early: Displaying two decimals is not always the same as rounding every calculation to cents. Excel may retain extra precision internally. For a lender-style schedule, round periodic interest and payment amounts as appropriate and reconcile the last payment.
• Ignoring payment timing or extra payments: A payment made on a different date, a variable rate, a skipped payment, or an additional principal payment changes the balance path. The simple formula does not represent these events.

A payoff estimate is not a payoff quote. A payoff quote can include interest accrued through a specific date and charges or adjustments not included in the formula. Check the loan documents or ask the lender for the exact payoff amount and how payments are applied.

Frequently Asked Questions

Can I use Excel to calculate a personal loan payoff?
Yes. Excel’s PMT function estimates a level monthly payment, and a table of monthly balances can show how principal and interest change over time. Add separate rows or inputs for extra payments if you need to model them.

What Excel formula calculates a personal loan payment?
For an APR stored as a decimal percentage, use =-PMT(APR/12, years*12, loan_amount). For a cell containing the number 8 to mean 8%, use =-PMT(8%/12, years*12, loan_amount) or divide the numeric APR by 1200.

Does this calculator include extra payments?
No. The two outputs assume equal scheduled payments and do not model additional principal. A month-by-month spreadsheet can include extra-payment amounts and update the balance after each payment.

Why is my Excel result different from the lender’s amount?
Differences can come from rounding, payment dates, daily interest accrual, fees, an adjusted final payment, or other contract terms. The formula is a general estimate, not a lender’s account calculation.

Is the total interest the same as the payoff amount?
No. Total interest is the estimated interest over the modeled term. The total of principal and interest is the estimated amount repaid, while a dated payoff quote may also account for accrued interest or other loan-specific items.

This result is an estimate, and the lender’s disclosure gives the exact figures.

Related

• National Average Personal Loan APR: What It Means
• Midwest Loan Services Payoff Request Calculator
• My LoanCare Payoff Request: Estimate Your Loan Balance

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
out pmt | Monthly payment | $ | p * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)) | 2
out int | Total interest | $ | pmt * yrs * 12 - p | 2