Rental Property Cash Flow Calculator
Calculate a rental's monthly and annual cash flow from rent, vacancy, other income, operating expenses, and the mortgage payment.
How to use this tool
- Enter the gross monthly rent at full occupancy.
- Set a realistic vacancy and credit-loss percentage.
- Add any other monthly income (parking, laundry, fees).
- Enter monthly operating expenses, including reserves, EXCLUDING the mortgage.
- Enter the monthly mortgage payment (principal + interest) and read the cash flow.
Will this rental feed you or bleed you? Enter rent, vacancy, other income, operating expenses, and the mortgage to see the monthly and annual cash flow the property actually generates.
Formula
Cash flow is what's left after every monthly cost, including the mortgage:
Effective gross income = Rent × (1 − Vacancy%) + Other income
Monthly cash flow = Effective gross income − Operating expenses − Mortgage
Annual cash flow = Monthly cash flow × 12
How it works
Cash flow is the money a rental actually puts in your pocket each month after all operating costs and the mortgage. Unlike NOI, it is an after-financing number, so it answers the practical question: will this property feed me or bleed me? Start from market rent, deduct a vacancy and credit-loss allowance, add ancillary income, then subtract operating expenses and the loan payment.
The most common error is omitting reserves. The operating-expense input should include realistic line items for property management, repairs and maintenance, and capital reserves for big-ticket replacements — not just taxes and insurance. A property that looks cash-flow positive on paper often turns negative once a vacancy, a turnover, or a roof replacement is factored in.
Reviewed by the AbraCalc Real Estate Desk. This model uses principal-and-interest for the mortgage; if taxes and insurance are escrowed in your payment, do not double-count them in operating expenses. This calculator provides general information, not investment advice; verify figures and assumptions against your own underwriting before acting.
Worked example
$2,000 rent, 5% vacancy, $50 other, $400 expenses, $1,100 mortgage
- Effective gross income = $2,000 × 0.95 + $50 = $1,900 + $50 = $1,950.
- Subtract expenses: $1,950 − $400 = $1,550.
- Subtract the mortgage: $1,550 − $1,100 = $450 monthly cash flow.
- Annual cash flow = $450 × 12 = $5,400.
Monthly cash flow $450.00 | Annual cash flow $5,400.00 | Effective gross income $1,950.00
Monthly cash flow at $2,000 rent (5% vacancy, $50 other), by expenses and debt
| Operating expenses | Mortgage | Monthly cash flow | Annual cash flow |
|---|---|---|---|
| $300 | $1,000 | $650 | $7,800 |
| $400 | $1,100 | $450 | $5,400 |
| $500 | $1,200 | $250 | $3,000 |
| $600 | $1,300 | $50 | $600 |
Key terms
- Cash flow
- Income remaining each period after all operating expenses and debt service.
- Effective gross income
- Rent after vacancy and credit loss, plus other income.
- Vacancy allowance
- A reserve for periods the unit is empty or rent goes uncollected, set as a percentage of rent.
- Capital reserves
- Money set aside for major future replacements like roofs, HVAC, and appliances.
Frequently asked questions
- What counts as good cash flow?
- Many investors look for at least $100-$200 of positive monthly cash flow per unit after all expenses and reserves, though targets vary widely by market and strategy. The key is that the number is positive after honest, fully-loaded expenses.
- Should I include property management and reserves?
- Yes. Even if you self-manage today, budget for management and for capital reserves so the analysis survives a vacancy, a turnover, or a major repair. Omitting them is the top cause of surprise negative cash flow.
- Is cash flow the same as profit?
- Not exactly. Cash flow is the actual money in and out. Accounting profit also reflects depreciation and other non-cash items. For a buy-and-hold investor, monthly cash flow is usually the more practical figure.