This rental property cash flow calculator estimates the money a rental produces after vacancy, operating expenses, debt payments and an allowance for capital replacements. It also shows NOI, annual cash flow, break-even rent and the collection rate needed to cover the budget.
Separate property performance from the owner's available cash. A rental can have positive NOI and still produce a cash deficit after financing. A positive bank balance can also overstate the money available to spend when the roof, HVAC or other capital items need a reserve.
How to use the rental cash flow calculator
- Enter scheduled monthly rent for the entire property before vacancy. Enter other income separately as an already-collected amount.
- Choose vacancy and collection loss from your own rent roll, lease-up plan and operating history. Do not apply this percentage again to a net collected-rent figure.
- Enter management as a percentage of collected rent. Maintenance and replacement-reserve allowances are percentages of scheduled rent in this model.
- Add annual property taxes and insurance, then monthly HOA dues, owner-paid utilities and other operating costs.
- Calculate a fixed-rate fully amortizing loan payment, or enter actual monthly debt service for a loan structure the automatic payment does not cover.
- Review the cash-flow breakdown and vacancy chart. Copy the link to preserve the input budget.
The defaults are an illustrative long-term rental, not expense benchmarks or an interest-rate quote. For a move-in month's tenant charge, use the prorated rent calculator; a partial first month and a stabilized monthly rental budget serve different purposes.
Rental property cash flow formula
collected rent = scheduled rent × (1 − vacancy ÷ 100)effective income = collected rent + other collected incomeNOI = effective income − operating expensescash flow before reserves = NOI − debt servicecash flow after reserves = NOI − debt service − replacement reserve
Fixed monthly expenses include taxes divided by twelve, insurance divided by twelve, HOA dues, utilities and other recurring costs. Management is collected rent times its percentage. Routine maintenance and capital reserves are each scheduled rent times their percentage. They do not automatically disappear when the property is vacant.
For the automatic loan payment, let r = annual note rate ÷ 1200 and n = term in months. Monthly principal and interest is loan × r ÷ [1 − (1 + r)^(−n)]. At zero interest it is simply loan divided by n. For an all-cash property, a zero loan means zero debt payment.
Worked example: $2,500 scheduled rent
Assume $2,500 monthly rent, 5% vacancy, $100 other collected income, management at 8%, maintenance at 5% and capital reserves at 5%. Annual property taxes are $3,600, annual insurance is $1,800, owner-paid utilities are $50 monthly and other operating costs are $50 monthly.
| Monthly budget | Amount |
|---|---|
| Collected rent after vacancy | $2,375.00 |
| Other collected income | +$100.00 |
| Effective income | $2,475.00 |
| Fixed operating costs | −$550.00 |
| Management | −$190.00 |
| Maintenance allowance | −$125.00 |
| NOI before financing and reserves | $1,610.00 |
| $180,000 loan, 6.5%, 30 years | −$1,137.72 |
| Replacement reserve | −$125.00 |
| Cash flow after reserves | $347.28 |
Annual NOI is $19,320.00 and annual cash flow after reserves is $4,167.33. Full precision is kept internally and displayed amounts are rounded, so summing visible cents can differ slightly from the displayed total.
Break-even occupancy and break-even rent
Break-even occupancy is the collected-rent share needed to cover the current budget. Because rent losses can include nonpayment as well as empty units, interpret it as an income-collection percentage. At the example assumptions it is 79.90%.
Let S be scheduled monthly rent, m the management fraction, F fixed costs, M the maintenance allowance, C capital reserves, D debt service and O other income. Required collection share is (F + M + C + D − O) ÷ [S × (1 − m)]. The displayed percentage multiplies that fraction by 100.
Break-even rent instead asks what scheduled rent would cover costs at the chosen vacancy percentage. It is (F + D − O) ÷ [(1 − vacancy) × (1 − management) − maintenance − reserve], using fractions for the percentages. Here the maintenance and reserve amounts scale with the new rent; the tool recalculates them rather than holding their current dollar values fixed.
The default break-even rent is $2,051.32. A nonpositive rent-contribution denominator has no positive-rent solution under these assumptions. If other income already covers the budget, the displayed minimum rent is zero. These results describe arithmetic feasibility, not market demand or a proposed rent increase.
Vacancy sensitivity and reserve planning
The chart and table change vacancy while keeping the other assumptions fixed. Lower rent collections also reduce the management fee under this model, but taxes, insurance, loan payments and scheduled-rent allowances continue.
| Rent loss | Monthly collected rent | Cash flow after reserves |
|---|---|---|
| 0% | $2,500.00 | $462.28 |
| 5% | $2,375.00 | $347.28 |
| 10% | $2,250.00 | $232.28 |
| 15% | $2,125.00 | $117.28 |
| 20% | $2,000.00 | $2.28 |
| 25% | $1,875.00 | -$112.72 |
With no capital reserve entered, monthly cash flow would display $472.28, which is $125.00 higher. That increase does not mean the building stops needing replacements. Use an inspection, ages of major systems, actual costs and funding plan to choose a reserve; the default percentage is only an illustration.
A steady monthly budget is not a payment calendar. Taxes and insurance may be paid annually, repairs occur unevenly, and vacancy can arrive as one long gap. Keep enough liquidity for those timing differences rather than assuming twelve equal positive months.
NOI, tax profit, cap rate and cash-on-cash return
This tool shows NOI before reserves and financing, then deducts both separately for available cash. Property-tax and insurance costs are counted once even when an escrow account pays them. The CFPB distinguishes principal and interest from the larger mortgage payment that can include those escrowed expenses.
IRS rental guidance distinguishes refundable deposits, repairs, improvements and depreciation. A refundable security deposit is not ordinary spendable rental income. Depreciation is not cash paid this month, and a major improvement is not automatically routine maintenance. Do not use this budget as a tax-return calculation.
Send annual NOI to the cap rate calculator to compare operating income with price. Send annual after-reserve cash flow to the cash-on-cash return calculator to evaluate invested cash. To compare a reduced loan payment after a lump sum, use the mortgage recast calculator.
Common mistakes and limitations
- Double-counting escrow. Enter taxes and insurance as operating costs and remove them from debt service.
- Ignoring repairs because none occurred recently. The maintenance allowance is a forecast, not proof that future work costs nothing.
- Counting maintenance and the same repair twice. Add a separate actual expense only after reconciling it with the allowance or reserve already included.
- Using a loan quote with the wrong term. A shorter amortization term can materially raise the cash payment even at the same rate.
- Treating the displayed coverage ratio as approval. It is NOI divided by debt service; lender underwriting may use different definitions.
Use actual debt-service mode for interest-only, balloon or other nonstandard loans and update it when payments change. The model does not forecast rent growth, appreciation, taxes on income, depreciation benefits, sale proceeds, staged renovations or per-unit lease timing. Short-term rentals with nightly occupancy, platform fees and seasonality need a more detailed operating budget.
Frequently asked questions
How do you calculate rental property cash flow?
Start with collected rent and other income, subtract property operating expenses, then subtract full debt service and planned capital reserves. Annual cash flow is the steady-state monthly result multiplied by twelve.
Does this include taxes and insurance?
Yes. Enter annual property tax and insurance premiums; the model divides them by twelve. Exclude their escrow portions from entered debt service so the same costs are not deducted twice.
What is the difference between NOI and cash flow?
NOI is property income after operating expenses and before debt service. Here capital reserves are displayed separately. Cash flow after reserves subtracts both debt service and the reserve allowance from NOI.
What is the example property's monthly cash flow?
With $2,500 scheduled rent, $100 other monthly income, 5% vacancy, the stated expense allowances and a $180,000 loan at 6.5% over 30 years, monthly cash flow after reserves is $347.28. Annual cash flow is $4,167.33.
Can I calculate an all-cash rental?
Yes. Set loan principal to zero. With the other default assumptions unchanged, after-reserve cash flow becomes $1,485.00 per month. This does not account for an alternative return on the cash used to buy the property.
How do I enter a duplex or a larger property?
Combine scheduled rents and expenses for all units. The vacancy percentage is an income-weighted rent loss assumption. The model does not forecast vacancy independently for each unit.
What does break-even occupancy mean?
It is the share of scheduled rent that must be collected to cover fixed expenses, scheduled-rent allowances, debt and reserves, after other income. It measures income collection, not necessarily the physical percentage of units occupied. Above 100% means the current rent cannot cover the modeled budget.
Does depreciation reduce cash flow?
Depreciation is not a cash payment, so it is excluded from this cash budget. Repairs, improvements, debt principal and taxes can affect cash and taxable income differently. This tool does not compute taxable rental profit.
Is the DSCR shown a lender qualification result?
No. It is simply the displayed NOI divided by debt service before reserves. Lenders may underwrite different rents, expenses, reserves and debt payments. The tool does not apply a lender's eligibility threshold.
Sources & method
- Fannie Mae — Form 4254 definitions: rental income, expenses, repairs, capital items and debt service (PDF)
- IRS Publication 527 — rental income, security deposits, repairs, improvements and depreciation
- CFPB — principal and interest vs total monthly mortgage payment
- Freddie Mac — amortization and published payment example
- OCC — Commercial Real Estate Lending handbook: cash-flow analysis and stress testing (PDF)
Results are estimates for general information. Found an error? It helps everyone — see our methodology.