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Commercial Mortgage Calculator
Estimating monthly payments on an income‑producing property isn’t as straightforward as a home loan. Commercial mortgages come with shorter terms, balloon payments, and underwriting that focuses on the property’s cash flow. The calculator above gives you a clear starting point: it computes your monthly principal‑and‑interest obligation, total interest over the life of the loan, and the balloon balance if the term is shorter than the amortization.
Enter your loan details to see how rate, term, and amortization shape your costs. Then use the debt‑service number to check whether the property’s net operating income will satisfy the lender’s coverage requirement.
How the Commercial Mortgage Calculator Works
The tool uses a standard amortization formula to determine the level monthly payment that fully repays the loan over the chosen amortization period. If the loan term is shorter than the amortization, the calculator also displays the remaining principal (balloon) due at maturity.
Payment formula:
\[ M = P \times \frac{r(1+r)^n}{(1+r)^n - 1} \]Where:
- \(M\) = monthly payment
- \(P\) = loan amount
- \(r\) = monthly interest rate (annual rate ÷ 12)
- \(n\) = total number of payments (amortization in years × 12)
After computing the payment, the tool builds an amortization schedule internally and extracts the unpaid balance at the end of the stated term. That balance is the balloon – a common feature in commercial lending.
Key Inputs for Your Calculation
Loan Amount
The total you plan to borrow. Lenders base this on the property’s appraised value and a maximum loan‑to‑value (LTV) ratio. For conventional commercial mortgages, LTV typically ranges from 65% to 80%.
Interest Rate
The annual percentage rate charged by the lender. Commercial rates are influenced by the index (e.g., SOFR or 5‑year Treasury), the lender’s spread, and the borrower’s credit profile. As of early 2026, well‑qualified borrowers see rates between 6.0% and 7.5% for standard commercial real estate loans.
Amortization Period
The number of years over which the loan’s payments are calculated as if it would be fully repaid. Common commercial amortizations are 20, 25, or 30 years. A longer amortization lowers each payment but increases total interest and often leaves a larger balloon if the term is short.
Loan Term
The length of time until the loan must be paid off or refinanced. Commercial loans frequently have terms of 5, 7, or 10 years, even though the amortization is longer. At the end of the term, the remaining balance becomes a balloon payment unless the loan is renewed or refinanced.
What Is DSCR and Why It Matters
Debt Service Coverage Ratio is the primary underwriting metric for commercial mortgages. It compares the property’s net operating income (NOI) to the total annual debt obligation:
\[ DSCR = \frac{\text{NOI}}{\text{Annual Debt Service}} \]Lenders typically require a minimum DSCR of 1.25x, meaning the property must generate 25% more net income than the mortgage payment. A higher DSCR signals lower risk and can help you negotiate a better rate.
After the calculator displays your annual debt service (monthly payment × 12), divide your projected NOI by that figure. If the result falls below the lender’s threshold, consider a larger down payment, a longer amortization, or a property with stronger cash flow.
Typical LTV Ratios for Commercial Mortgages
- Conventional bank loans: 65–80% LTV
- SBA 7(a) loans: up to 85% LTV for owner‑occupied properties
- SBA 504 loans: up to 90% LTV (with a 50% first mortgage and 40% CDC portion)
- Life company / CMBS loans: 60–75% LTV, often for stabilized, high‑quality assets
LTV directly affects the down payment you must bring. A property valued at $2,000,000 with a 75% LTV cap requires a $500,000 equity injection.
Commercial vs Residential Mortgage: Key Differences
- Underwriting focus: Commercial loans are underwritten based on the property’s income, not the borrower’s personal income alone.
- Term and amortization: Residential mortgages often have 30‑year terms that match the amortization. Commercial loans frequently have a 5–10‑year term with a 20–30‑year amortization, creating a balloon.
- Prepayment penalties: Commercial mortgages almost always carry yield maintenance or step‑down prepayment penalties, while residential loans rarely do.
- Interest rates: Commercial rates are typically higher than residential rates and may float or fix for a shorter period.
- Loan structure: Many commercial loans are interest‑only for a portion of the term, which this calculator does not model, but it gives a baseline for full amortization scenarios.
Factors That Affect Your Interest Rate
Lenders price commercial mortgages based on several criteria:
- LTV and DSCR: Lower leverage and higher coverage improve pricing.
- Property type: Multifamily and anchored retail usually receive lower rates than hotels, restaurants, or special‑purpose buildings.
- Borrower strength: Net worth, liquidity, and experience with similar assets matter.
- Loan size: Larger loans often get better rates due to economies of scale.
- Economic environment: In early 2026, rates remain elevated relative to the 2020–2021 period. Check current indices when modeling.
Example: 10‑Year Term, 25‑Year Amortization
Assume a $1,500,000 loan at 6.75% fixed for 10 years, amortized over 25 years.
- Monthly payment: ≈ $10,365
- Annual debt service: $124,380
- Balloon after 10 years: ≈ $1,130,000
If the property produces an NOI of $160,000, the DSCR is 1.29x – right above the typical minimum. The calculator allows you to adjust any variable and instantly see how the payment, total interest, and remaining balance change.
Rates and terms are illustrative. Actual mortgage terms depend on market conditions, lender policies, and your financial profile. Consult a commercial mortgage professional for personalized quotes.
Frequently Asked Questions
What is a commercial mortgage calculator?
A commercial mortgage calculator is a tool that estimates monthly loan payments for income‑producing properties like office buildings, retail centers, and multifamily housing. It factors in loan amount, interest rate, amortization, and often calculates the debt service coverage ratio (DSCR).
How do I calculate DSCR for a commercial loan?
DSCR is net operating income (NOI) divided by total annual debt service. Most lenders require a minimum DSCR of 1.25x. The calculator above computes your annual debt obligation; compare it to the property’s NOI to see if the cash flow supports the loan.
What is a typical interest rate for a commercial mortgage in 2026?
As of early 2026, commercial mortgage rates for strong‑credit borrowers range from about 6.0% to 7.5% for conventional loans. SBA 7(a) and 504 loans may carry slightly higher spreads. Rates vary with property type, LTV, and DSCR strength.
What loan‑to‑value ratio do commercial lenders require?
Most conventional commercial lenders cap LTV at 65–80%, meaning a 20–35% down payment. Special‑purpose properties or higher‑risk loans may require an even lower LTV. SBA 504 loans can go up to 90% LTV in certain cases.
Can I use this calculator for SBA 7(a) or 504 loans?
Yes. The calculator works for any fully amortizing commercial loan, including SBA programs. For 504 loans with a 10‑ or 20‑year fixed‑rate piece, enter the appropriate term and rate; note that 504 structures often include a balloon, which this basic version does not model automatically.
Does the calculator include balloon payments?
This calculator assumes full amortization over the selected period. Many commercial mortgages have a shorter term (e.g., 10 years) with a 25‑year amortization schedule, leaving a balloon balance. The tool shows the remaining principal at the end of the term, which represents that balloon.
How does amortization affect my commercial mortgage payment?
Longer amortization (e.g., 25–30 years) lowers the monthly payment but increases total interest. A shorter schedule saves interest but raises the payment. The calculator lets you compare how amortization length changes both the payment and the balloon at the end of the term.