Rental Cash Flow Calculator
The Rental Cash Flow Calculator gives you a detailed, line-by-line breakdown of monthly and annual cash flow for any rental property. Input your rent, vacancy rate, property management fee, taxes, insurance, maintenance, mortgage payment, and any other expenses to see exactly how much cash the property generates — or costs — each month. Positive cash flow is the foundation of any sustainable rental investment strategy.
Gross rent at full occupancy
Expected percentage of time vacant (5% ≈ 18 days/year)
% of effective rent charged by property manager (0 if self-managing)
Annual property tax bill
Annual landlord insurance premium
Estimated annual repairs and routine maintenance (~1% of property value)
Principal + interest only. Enter 0 if paying cash.
HOA dues, utilities, lawn care, etc.
Monthly Cash Flow
$227.00
Annual Cash Flow
$2,724.00
Effective Monthly Rent (after vacancy)
$2,280.00
Total Monthly Expenses
$2,053.00
How to use this calculator
- 1
Enter monthly rent
Enter the gross monthly rent at full occupancy. For multi-unit properties, enter the total combined rent for all units.
- 2
Set vacancy rate
The percentage of time the property is expected to sit empty. A 5% vacancy rate is equivalent to about 18 days per year. Single-family rentals in tight markets may see 2–3%; less desirable properties may experience 8–10%+.
- 3
Enter property management fee
If you hire a property manager, they typically charge 8–12% of collected rent. If you self-manage, set this to zero. The calculator applies this fee to effective rent (after vacancy), as most managers only charge on collected rent.
- 4
Enter annual property tax, insurance, and maintenance
Input these annually — the calculator divides them by 12 for the monthly view. Maintenance is often estimated at 1% of property value per year, though older properties may run higher.
- 5
Enter monthly mortgage payment and other expenses
Enter the full principal + interest payment if the property is financed. Add any other recurring monthly expenses such as HOA dues, utilities, or lawn care.
- 6
Review your monthly and annual cash flow
The calculator shows effective rent after vacancy, total monthly expenses, monthly cash flow, and annual cash flow. Positive values in green mean the property produces income; negative values in red mean it costs you money each month.
Formula
Effective Monthly Rent = Monthly Rent × (1 − Vacancy Rate / 100)
Management Fee = Effective Monthly Rent × (Management % / 100)
Total Monthly Expenses =
(Annual Property Tax / 12)
+ (Annual Insurance / 12)
+ (Annual Maintenance / 12)
+ Management Fee
+ Monthly Mortgage Payment
+ Other Monthly Expenses
Monthly Cash Flow = Effective Monthly Rent − Total Monthly Expenses
Annual Cash Flow = Monthly Cash Flow × 12Effective rent adjusts gross rent for expected vacancy before calculating management fees, since managers typically charge only on collected rent. All annual expenses (tax, insurance, maintenance) are prorated monthly. The result is a realistic bottom-up model of monthly net income. Example: $2,400/month rent, 5% vacancy → $2,280 effective rent. With $1,600/month total expenses, monthly cash flow = $680 and annual cash flow = $8,160.
Worked Example
Monthly Rent: $2,400 Vacancy Rate: 5% Effective Monthly Rent: $2,280 Property Management (10%): $228 Property Tax (annual $4,200): $350/mo Insurance (annual $1,500): $125/mo Maintenance (annual $2,400): $200/mo Mortgage Payment: $1,100/mo Other Expenses: $50/mo Total Monthly Expenses: $2,053 Monthly Cash Flow: $2,280 − $2,053 = $227 Annual Cash Flow: $227 × 12 = $2,724 This property generates positive cash flow, but the margin is thin — vacancy or an unexpected repair could push it negative temporarily.