Commercial Mortgage Calculator

Find out what your commercial real estate loan will actually cost — monthly payment, total interest, and the balloon balance due at maturity. Works for any property type: multifamily, office, retail, industrial, mixed-use, or special purpose.

Just enter your loan amount, interest rate, loan term, and amortization period. Commercial loans almost always have a shorter term than amortization (e.g., a 10-year term on a 30-year amortization schedule), which creates a balloon payment at maturity. This calculator handles that correctly.

How to Use This Calculator

Loan Amount

The total mortgage balance — not the purchase price. If you’re purchasing a $2M property with 25% down, your loan amount is $1.5M. For a refinance, use your current or proposed payoff balance.

Interest Rate

Enter the annual interest rate on the loan. For a rate quote specific to your property, contact a RefiLoop broker — commercial rates vary by loan type, property class, and borrower strength.

Loan Term vs. Amortization Period

This is where commercial loans differ from residential:

• Amortization period — how long your payment schedule is based on (usually 25–30 years)
• Loan term — how long until the loan matures and the balance is due (often 5, 7, or 10 years)

When the term is shorter than the amortization period, the remaining balance becomes a balloon payment due at maturity. Most borrowers either refinance or sell before that date.

Interest Only

Select “Interest Only” for the amortization period if you want to model a loan where no principal is paid down. Common in bridge loans and some construction loans. The entire original balance becomes the balloon.

Understanding Your Results

Monthly Payment

Your regular principal and interest (P&I) payment. This does not include property taxes, insurance, or HOA/management fees — those are paid separately and factor into your NOI and DSCR calculation.

Annual Debt Service

Total P&I over 12 months. Lenders use this number — along with your Net Operating Income — to calculate your DSCR. A DSCR of 1.25x is the standard minimum for most commercial loans. Use our DSCR Calculator to check if your property qualifies.

Balloon Payment

The remaining principal balance due when the loan matures. For a $1.5M loan on a 30-year amortization with a 10-year term, the balloon after 10 years is roughly $1.2M. Plan ahead: start exploring refinance options 12–18 months before your balloon date.

LTV Ratio

Loan-to-value is the loan amount divided by the property’s appraised value. Most lenders cap LTV at:

• 75% — multifamily, anchored retail, industrial
• 70% — office, unanchored retail, mixed-use
• 65% — special purpose, hospitality, construction
• 90% — SBA 504 loans (owner-occupied only)

Bridge Financing Considerations

If you’re between properties or need quick acquisition capital, commercial bridge loans offer temporary financing at higher rates with interest-only payments. Bridge loans typically last 12–36 months and allow you to close fast before permanent financing is arranged. Use this calculator with Interest Only amortization and a short (1–3 year) term to model a bridge scenario, then calculate your permanent take-out loan payment separately.

Commercial Loan Types This Calculator Works For

• Multifamily loans — 5+ unit apartment buildings, typically 30-year amortization, 5–10 year terms
• CMBS loans — non-recourse, 25–30 year amortization, 10-year term standard
• SBA 504 loans — owner-occupied only; second mortgage fully amortizing over 20–25 years
• Bridge loans — typically interest-only, 1–3 year terms
• Balloon refinances — calculate your new payment after rolling over a maturing balloon
• Construction loans — model the take-out/permanent financing phase

Frequently Asked Questions

What is a typical commercial mortgage interest rate?

Commercial rates vary by loan type, property class, LTV, and borrower profile. As a general benchmark, conventional commercial loans have historically ranged from roughly 1–2% above comparable Treasury yields. SBA 504 rates are tied to 5- and 10-year Treasury rates plus a small spread. Bridge loans carry higher rates to compensate for short-term, higher-risk lending. For a current rate quote on your specific deal, contact RefiLoop — rates change weekly.

How is a commercial mortgage payment calculated?

The payment uses the standard amortization formula: P × r / (1 − (1 + r)^−n), where P is the loan balance, r is the monthly interest rate (annual rate ÷ 12), and n is the number of months in the amortization period. After the loan term ends, any remaining balance is due as a balloon payment rather than continuing to be paid down.

What amortization period should I use?

Most conventional commercial loans use a 25- or 30-year amortization. SBA 504 loans are fully amortizing over 20 or 25 years. CMBS loans commonly use 30-year amortization with a 10-year term. Shorter amortization periods mean higher monthly payments but less interest paid overall and a smaller balloon balance.

Does this include taxes, insurance, and other costs?

No — this calculator shows principal and interest only. Property taxes, insurance, property management fees, and maintenance costs are excluded. Those expenses reduce your gross income to arrive at NOI, which is a separate calculation.

What happens if I can’t pay the balloon?

A balloon coming due without a refinance plan is called “balloon risk.” Options include: (1) refinancing into a new commercial mortgage before maturity, (2) selling the property, (3) negotiating a loan extension with the existing lender, or (4) obtaining a short-term bridge loan to buy time. Start working on your exit 12–18 months before the balloon date. RefiLoop can help you refinance — start here.

Can I use this for an SBA loan?

Yes — for the SBA 504 program, the second mortgage (the CDC portion, typically 40% of the project cost) is fully amortizing over 20 or 25 years with no balloon. Enter the 504 second mortgage amount, current SBA rate, and set both term and amortization to 20 or 25 years. The bank first mortgage (50% of project) typically has a 10-year balloon on a 25-year amortization — calculate that separately.

How do I know if my NOI covers this payment?

Use our DSCR Calculator. Lenders divide NOI by annual debt service — if that ratio is 1.25x or higher, you meet the standard qualification threshold.

Commercial Mortgage Brokerage — RefiLoop

RefiLoop is a commercial mortgage broker (NMLS #2510864) placing loans on 4+ unit and commercial properties across 39 states. We work with banks, credit unions, CMBS conduit lenders, SBA CDCs, and private bridge lenders to find the right loan for your property and deal profile. Consultations are free — get started here.