Business Loan Amortization Table Calculator

A business loan amortization table shows how each scheduled payment is divided between principal and interest, along with the remaining balance. Enter the loan amount, annual interest rate, and term to calculate an estimated monthly payment and total interest; the table itself can be built from those figures one month at a time.

Formula

This calculator uses the standard fixed-rate loan payment formula. It assumes equal monthly payments and a constant annual percentage rate (APR), converted to a monthly rate.

• Monthly rate: r = APR / 1,200, where APR is entered as a percentage per year.
• Number of payments: n = loan term in years × 12.
• Monthly payment: M = P × r / [1 − (1 + r)⁻ⁿ].
• Total interest: I = M × n − P.

P is the starting principal in dollars, r is the monthly rate as a decimal, n is the number of monthly payments, M is the monthly payment in dollars, and I is the total interest in dollars. The calculator rounds the displayed monthly payment to cents. Its total-interest expression uses that displayed, rounded payment multiplied by the number of scheduled payments, then subtracts principal. Actual lender schedules can differ because of payment dates, rounding conventions, fees, or other contract terms.

Worked Example

Using the calculator’s default inputs—$20,000 principal, 8% APR, and a five-year term—the loan has 60 scheduled monthly payments.

1. Convert the APR to a monthly decimal rate: 8 ÷ 1,200 = 0.0066667.
2. Substitute the inputs: M = 20,000 × 0.0066667 ÷ [1 − (1 + 0.0066667)⁻⁶⁰].
3. The unrounded payment is about $405.53, so the monthly payment rounded to cents is $405.53.
4. Calculate total interest using the rounded payment: $405.53 × 60 − $20,000 = $4,331.80.

The calculation gives an estimated payment of $405.53 per month and total interest of $4,331.80 over the scheduled term. A lender’s exact final payment can vary slightly if it adjusts the last installment to account for rounding or the actual payment calendar.

Assumptions

• The interest rate is fixed for the full term, and the loan is repaid in equal monthly installments.
• Payments are modeled monthly; interest compounds monthly at APR divided by 12.
• The calculator does not include fees, taxes, insurance, PMI, escrow, or other charges. It also does not model variable rates, irregular payments, or a changing balance from new borrowing.

How to Read an Amortization Table

An amortization table lists one row for each payment period. A typical row includes the payment number or date, the amount paid, the interest portion, the principal portion, and the balance remaining after payment. The rows explain why a payment can remain level even though its components change.

For a standard monthly schedule, estimate the interest in a period by multiplying the balance before payment by the monthly rate. Subtract that interest from the scheduled payment to find the principal reduction. Then subtract the principal reduction from the previous balance. In symbols, for payment k:

• Interest for the period ≈ balance before payment × r.
• Principal repaid ≈ payment − interest for the period.
• New balance ≈ previous balance − principal repaid.

With the example’s initial balance of $20,000 and monthly rate of about 0.0066667, first-month interest is about $133.33. Of the $405.53 payment, roughly $272.20 reduces principal, leaving an estimated balance of $19,727.80. Later, the balance is smaller, so the interest portion generally falls and more of the same payment goes to principal. Displayed cents may make a reconstructed schedule differ by a few cents from a lender’s statement.

When to Use the Calculator

Use this estimate to understand the basic payment pattern for a proposed fixed-rate business loan, compare different principal or term assumptions, or check how much interest the stated payment schedule implies. It can also help when reviewing a lender-provided schedule: compare the stated principal, APR, payment frequency, and term with the assumptions used here before interpreting differences.

For a complete amortization table, generate a row for every payment using the balance-and-interest steps above, keeping full precision internally and rounding displayed currency to cents. The final row should bring the balance to zero, subject to the lender’s final-payment adjustment. This calculator provides the payment and total-interest estimate, not a date-specific table; payment dates and the lender’s accrual method are needed to reproduce the exact schedule.

Common Errors and Limits

• Entering 8 instead of 0.08 in a different formula: This calculator expects APR as a percentage, so enter 8 for 8%. It converts the value internally.
• Mixing annual and monthly periods: The rate is converted to a monthly rate and the term in years to months. Do not enter a monthly rate as the APR.
• Assuming the payment includes every cost: A loan payment estimate excludes any costs not entered in the formula. Check the lender’s disclosure for the actual payment obligation and any separately charged amounts.
• Treating the estimate as an exact payoff quote: A payoff amount can depend on the date, accrued interest, fees, and contract terms, none of which are modeled here.

The fixed-payment formula does not represent a variable-rate loan, a loan with interest-only or balloon periods, payment holidays, additional principal payments, or fees added to the balance. For those cases, the schedule must reflect the loan’s actual terms and payment timing. The rate and term are inputs only; obtain the applicable figures and schedule from the lender rather than treating the example defaults as market information.

Frequently Asked Questions

What is a business loan amortization table?
An amortization table is a period-by-period record of scheduled payments, interest charged, principal repaid, and the remaining loan balance. It shows how repayment progresses over the stated term.

How do I calculate the interest portion of a monthly payment?
For a standard monthly schedule, multiply the balance immediately before the payment by the monthly interest rate. The remaining part of the payment is principal, assuming no separate charges are included in that payment.

Why does the principal portion increase over time?
As principal is repaid, the balance used to calculate interest falls. With a constant rate and level payment, less of each later payment goes to interest and more goes to principal.

Does this calculator include fees or a balloon payment?
No. It models a fully amortizing loan with equal monthly payments and does not include fees, a balloon payment, or other nonstandard payment features. Use the written loan terms for those details.

Why might my lender’s table differ by a few cents?
Lenders may use different rounding rules, payment dates, or interest-accrual methods, and they may adjust the final installment. The calculator is a simplified estimate rather than a reproduction of a lender’s servicing system.

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

Related

• Simple Interest Loan Amortization Table Calculator
• Amortization Table Software: Calculate Loan Payments
• Amortization Table Setup: Formula and Example

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