Investment Mortgage Calculator
Compute your principal & interest payment, total interest over the life of the loan, and a full year-by-year amortization schedule. Built for investors — does not include taxes or insurance (those are separate).
Loan Details
Calculates principal & interest only — taxes and insurance are separate.
20% conventional, 25% for investment property DSCR loans.
Monthly P&I
principal & interest, monthly
How a mortgage payment is calculated
A fixed-rate mortgage is a level-payment amortizing loan. Each payment splits between interest (computed on the remaining balance) and principal (which reduces the balance). At the start, almost all of the payment is interest; by the end, almost all of it is principal.
The formula
Investment-property specifics
- Down payment: 20% conventional minimum; 25%+ for DSCR loans.
- Rate premium: typically 0.5–1% above primary residence; DSCR another 0.5–1.5% higher.
- Term: 30-year fixed maximizes cash flow; 15-year saves interest but cuts cash flow.
- PMI: not available on investment property — you must put 20%+ down.
Frequently asked questions
How is a mortgage payment calculated?
Monthly P&I = P × [r × (1 + r)^n] ÷ [(1 + r)^n − 1], where P is the loan principal, r is the monthly interest rate (annual rate ÷ 12), and n is the number of payments (years × 12). The result is a fixed monthly payment that pays off the loan over the term.
Does this include taxes and insurance?
No. This calculator shows principal & interest (P&I) only. Property taxes, homeowners insurance, HOA, and PMI are separate. For a full housing payment, add taxes (1–2% of property value annually) and insurance (0.5–1%) divided by 12.
What loan term should I use for an investment property?
30 years is most common — lower payment maximizes monthly cash flow. 15 years saves on total interest but cuts cash flow in half. DSCR loans are typically 30-year fixed with optional interest-only periods.
How does a higher down payment change the math?
A larger down payment lowers the loan balance, which lowers the monthly payment proportionally. It also reduces total interest paid over the life of the loan and improves DSCR (better lender approval odds).
Why do investment property rates run higher than primary?
Lenders price investment loans 0.5–1% higher than owner-occupied because the borrower is more likely to walk away if cash flow turns negative. DSCR loans (no income verification) run another 0.5–1.5% higher on top of that.
Should I pay points to lower my rate?
Run the math. One point typically costs 1% of loan balance and lowers the rate by 0.25%. Compute the monthly savings, then divide the upfront cost by the monthly savings to get break-even months. If you’ll hold the property longer than that, points pay off.
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