Investing in a duplex, triplex, or apartment complex? Use this multifamily mortgage calculator to estimate your monthly debt service based on investment loan rates and down payment requirements.
Multifamily Mortgage Calculator
Multifamily Mortgage Calculator Formula
The monthly payment for multifamily properties is calculated using the standard amortization formula. However, for commercial loans (5+ units), amortization periods may differ from the loan term (e.g., a 25-year amortization with a 10-year balloon payment):
Variables
- M: Monthly Principal & Interest Payment.
- P: Principal Loan Amount (Price – Down Payment).
- i: Monthly Interest Rate (Annual Rate / 12).
- n: Amortization Period in Months.
Related Calculators
- DSCR Calculator
- Cap Rate Calculator
- Net Operating Income (NOI) Calculator
- Commercial Loan Calculator
What is Multifamily Mortgage Calculator?
A multifamily mortgage calculator helps investors crunch the numbers on properties with more than one unit. There are two main categories of multifamily financing:
- Residential (2-4 Units): Treated similarly to standard home loans. You can often use FHA (3.5% down) or Conventional (15-25% down) financing with 30-year fixed terms.
- Commercial (5+ Units): Treated as a business loan. Interest rates are typically higher, down payments usually start at 25-30%, and terms are often shorter (e.g., 5, 7, or 10 years) even if amortized over 20-25 years.
How to Calculate Multifamily Mortgage (Example)
Example for a $850,000 4-plex (Residential loan rules):
- Down Payment: 25% ($212,500) is standard for investment properties.
- Loan Principal: $850,000 – $212,500 = $637,500.
- Interest Rate: Investment rates are higher than primary rates, e.g., 7.5%.
- Term: 30 years.
- Result: The P&I payment is approximately $4,457.36 per month.
Frequently Asked Questions (FAQ)
Yes. For both residential (2-4 unit) and commercial loans, lenders typically allow you to use 75% of the projected rental income to help qualify for the mortgage (offsetting the debt).
Debt Service Coverage Ratio (DSCR) is a key metric for commercial multifamily loans. It measures the property’s ability to pay its own debt. A DSCR of 1.25 means the Net Operating Income is 1.25 times the mortgage payment.
Yes. Investment property loans generally carry interest rates 0.50% to 1.00% higher than primary residence loans due to the increased risk of default.
Yes! This is called “house hacking.” If you live in one unit of a 2-4 unit property, you can qualify for owner-occupied financing (like FHA) with much lower down payment requirements (as low as 3.5%).