Commercial Loan Calculator

How Commercial Loan Calculations Work

Commercial real estate loans use a standard amortization formula to calculate monthly payments, but they frequently feature a shorter loan term than the amortization schedule. This structure results in a balloon payment — a lump sum of remaining principal due when the term expires.

Monthly Payment Formula

The monthly payment is calculated using the standard amortizing payment formula based on the full amortization period, not the loan term. The formula is: P = L [i(1+i)^n] / [(1+i)^n – 1], where L is the loan amount, i is the monthly interest rate, and n is the total number of amortization months.

Balloon Payment

When the loan term is shorter than the amortization period, the outstanding principal balance at the end of the term becomes the balloon payment. This is calculated using a standard loan amortization table to find the remaining balance after the term payment count. Most commercial borrowers refinance at balloon maturity.

Loan-to-Value (LTV)

LTV is the loan amount divided by the property value. Commercial lenders typically require LTV of 65% to 80% depending on property type, loan program, and borrower strength. Lower LTV means lower lender risk and often better rate terms.

Debt Service Coverage Ratio (DSCR)

DSCR is the property annual NOI divided by annual debt service (total yearly loan payments). A DSCR of 1.00 means the property just breaks even. Most commercial lenders require a minimum DSCR of 1.20 to 1.25, with SBA programs sometimes accepting 1.15 or higher.

SBA Loan Programs

The SBA 7(a) program offers up to $5 million for business real estate and equipment, with terms up to 25 years and full amortization (no balloon). The SBA 504 program is structured with a conventional first mortgage covering approximately 50% of the project cost, a certified development company (CDC) second lien covering 40%, and a 10% borrower equity injection. Both programs are partially government-guaranteed, which typically allows lower down payments and competitive rates.

Bridge and CMBS Loans

Bridge loans are short-term financing (typically 1 to 3 years) used for transitional properties, acquisitions, or value-add scenarios. Interest rates are higher and full amortization is uncommon. CMBS (Commercial Mortgage-Backed Securities) loans are pooled and sold to bond investors — they are non-recourse, typically have 10-year terms with 25 to 30 year amortization, and carry prepayment penalties (defeasance or yield maintenance).

Choosing Between Loan Programs

The right commercial loan structure often depends on how long you plan to hold the property and how much certainty you need around the exit. A balloon-structured conventional loan can offer a lower rate, but it requires refinancing or a sale before maturity, so it works best when you have a clear plan for that point in time.

SBA programs can be attractive for owner-occupied properties because of their fuller amortization and lower down payment requirements, but they involve more documentation and government-guarantee underwriting. Bridge and CMBS loans serve more specialized situations, such as a property in transition or a larger, longer-term hold, and it is worth discussing your specific NOI, LTV, and timeline with a commercial lender before settling on a structure.