Rental Property Cash Flow Calculator
This rental property cash flow calculator shows the money left over each month after rent pays your mortgage and every operating cost. Cash flow is rental income minus all operating expenses minus debt service. Enter your numbers in the calculator above to find out if a property turns a real monthly profit. The result tells you whether the deal feeds your bank account or drains it.
How it's calculated
The calculator above turns rent and costs into monthly cash flow using a simple formula. It starts with gross rent, then subtracts vacancy loss to get effective gross income. From there it removes operating expenses like taxes, insurance, maintenance, and management to reach net operating income (NOI). Finally it subtracts your loan payment to show monthly cash flow.
You enter the purchase price, down payment, loan terms, rent, and expense rates. The tool handles the math and returns cash flow, cap rate, cash-on-cash return, and DSCR. Each metric answers a different question about the deal.
A worked example
Consider a single-family rental priced at $240,000 with 25% down. The $180,000 loan at 6.75% over 30 years costs $1,167 a month in principal and interest. Rent is $2,300 a month, or $27,600 a year in gross rent. After 5% vacancy, effective gross income is $26,220. Operating expenses, including $2,800 in taxes, $1,300 in insurance, and 8% each for maintenance and management, total $8,516 a year. That leaves net operating income of $17,704. Subtract the annual debt service and cash flow is $308 a month, or $3,694 a year. With $67,200 invested, that is a 5.5% cash-on-cash return, a 7.38% cap rate, and a DSCR of 1.26.
Common mistakes to avoid
- Skipping vacancy. No rental stays full every month. Budget around 5% of gross rent so a single empty month does not erase your profit.
- Forgetting maintenance and capital reserves. If you ignore repairs and big-ticket items like a roof or HVAC, your reported cash flow is fake. Set aside a percentage of rent every month.
- Leaving out management fees when you self-manage. Your time has value. Include a management line so the deal still works when you hand it off later.
- Counting only principal and interest. Taxes and insurance are real cash costs. Add them to your loan payment to see true monthly cash flow.
- Confusing cash flow with NOI. NOI ignores your mortgage. Cash flow is what lands in your pocket after debt service.
Frequently asked questions
What is a rental property cash flow calculator?
A rental property cash flow calculator shows your monthly profit after rent pays the mortgage, taxes, insurance, vacancy, maintenance, and management. It tells you whether a property makes or loses money each month. The calculator above does this math for you.
How do you calculate rental cash flow?
Rental cash flow equals rental income minus all operating expenses minus your loan payment. Start with gross rent, subtract vacancy, then subtract operating costs to get NOI. Subtract debt service from NOI to reach cash flow. In our example, that comes to $308 a month.
What is a good monthly cash flow for a rental?
A good rental produces positive cash flow after every expense, including reserves for repairs and capital costs. Many investors aim for a comfortable cushion per unit. Our example deal returns $308 a month and a 5.5% cash-on-cash return.
Does cash flow include the mortgage payment?
Yes. Cash flow subtracts your full debt service, including principal and interest. This is the key difference from net operating income, which ignores the loan. NOI in our example is $17,704, but cash flow is $3,694 a year after the mortgage.
What DSCR do lenders want for a rental property?
Lenders typically want a debt service coverage ratio of at least 1.2, meaning NOI covers the loan payment with room to spare. Our example deal has a DSCR of 1.26, which clears that bar. A higher DSCR signals a safer loan. See the cap rate calculator and cash-on-cash return calculator for the other metrics.