How the loan length is worked out
Each month interest accrues on the balance at the note rate divided by 12, and then your payment comes off. The loan is paid off when the balance reaches zero. The number of payments n comes from the balance B, the monthly rate i and the payment M: n = -ln(1 - i × B ÷ M) ÷ ln(1 + i), rounded up. The last payment is smaller than the others because it only clears what is left.
If your payment is no more than the first month's interest, the balance never falls and there is no payoff date. Lenders also differ on how an extra payment is applied, so confirm that yours goes to principal.
Worked example: $500,000 at $4,200 a month
A $500,000 balance at 7.5% with a payment of $4,200 a month is paid off in 219 payments, which is 18 years and 3 months. The final payment is $3,038.77. With the first payment on December 1, 2026, the last payment falls on February 1, 2045. You pay $418,638.77 of interest, and $918,638.77 in total.
What extra payments save
Adding $300 a month takes the payment to $4,500 and pays the loan off in 191 payments, which is 15 years and 11 months, with the last payment on October 1, 2042. That saves 2 years and 4 months and $62,321.95 of interest.
The payment that pays the loan off in a target term
To pay off the same $500,000 in 10 years, the payment has to be $5,935.09 a month, which is $1,735.09 more than $4,200. Over those 10 years you would pay $212,210.61 of interest and $712,210.61 in total. If your payment is already above the one needed, the calculator shows by how much. At $6,500 a month the loan is paid off in 106 payments, and your payment is $564.91 above the $5,935.09 needed for 10 years.
What this calculator leaves out
This is a planning calculator for a fixed rate and a level monthly payment. It does not model a variable rate, a balloon payment, an interest-only period, a prepayment penalty or fees. Many commercial loans amortize over a longer period than the loan term, which leaves a balloon due at maturity. Use the balloon calculator for that case.
For a loan with a balloon at maturity, use the commercial loan balloon payment calculator .
For a payoff with a settlement date and prepayment charge, use the business loan payoff calculator .
Use the right country page
This page stays in US dollars and uses US terms and the US date format. The country choices above the inputs open separate local pages. Choosing United Kingdom opens the UK commercial loan length calculator, in pounds. The inputs reset and amounts are not converted.
Inputs for the US commercial loan length calculator
Loan balance
The amount owed now, or the amount you are borrowing.
Interest rate
The yearly note rate, charged monthly at one twelfth.
Monthly payment
What you pay each month toward the loan, before any extra.
Extra payment each month
An overpayment added to every monthly payment. Enter zero for none.
Target term
The time you want the loan gone in, in whole months. We find the monthly payment that does it.
First payment date
When the next payment is due. We date the last one from it.
CALCULATOR QUESTIONS
US commercial loan length calculator questions
How long will it take to pay off my commercial loan?
Enter the balance, the rate and your monthly payment. $500,000 at 7.5% with $4,200 a month takes 219 payments, 18 years and 3 months.
How do I find the payoff time from the payment?
Use n = -ln(1 - i × B ÷ M) ÷ ln(1 + i), where B is the balance, i the monthly rate and M the payment, and round up. The calculator does this for you.
What payment pays a loan off in 10 years?
For $500,000 at 7.5%, $5,935.09 a month pays the loan off in 10 years. Change the target term to see the payment for any other length.
How much do extra payments save?
An extra $300 a month on that loan saves 2 years and 4 months and $62,321.95 of interest. Check that your lender applies extra money to principal and has no prepayment penalty.
Why does it say my payment is too low?
A payment that does not cover a month's interest never reduces the balance. At 7.5% on $500,000 the first month's interest is $3,125.00, so the payment must be higher.
Are fees included?
No. A fee paid on its own does not change how many payments you make, so it is left out of the payoff time. It still adds to the cost, so allow for it when comparing loans.
What happens when I change country?
The United Kingdom option opens the separate commercial loan length calculator, in pounds. Your inputs are reset rather than converted.