Rental Property Cash Flow Calculator
Work out a rental property’s monthly cash flow after mortgage, taxes, insurance, repairs and management, with cap rate, cash-on-cash, DSCR and break-even rent.
Cash flow is what a rental puts in your pocket each month after every bill, including the mortgage. A property can look profitable on rent alone and still lose money once vacancy, repairs, big-ticket replacements and management are counted. This calculator lays out each line monthly and yearly and adds the ratios lenders and investors check.
How to use this tool
- Enter the price, down payment, closing costs, mortgage rate and term.
- Enter the monthly rent, any other income and a vacancy allowance.
- Fill in property tax, insurance, HOA and any utilities you pay.
- Set repairs, capital reserve and management as percentages.
Formula
Cash flow = (rent + other) × (1 − vacancy) − operating expenses − capital reserve − mortgage payment
NOI deducts tax, insurance, HOA, utilities, repairs and management. Capital reserve is deducted after NOI, then debt service gives cash flow. Cap rate uses NOI before reserve; both NOI-based and post-reserve coverage are shown. Break-even means the minimum nonnegative rent covering modeled outflows.
Example
A $250,000 house with 25% down leaves a $187,500 loan; at 7% for 30 years the payment is $1,247.44. Rent of $2,200 minus 5% vacancy gives $2,090. Tax ($250), insurance ($116.67), repairs and capital reserve (5% each, $110 + $110) and 8% management ($167.20) cost $753.87 a month, so NOI before the $110 capital reserve is $1,446.13 and cash flow is $88.69 a month ($1,064.29 a year). NOI-based coverage is 1.16; coverage after reserve is 1.07 and the minimum whole-cent break-even rent is $2,085.42.
Frequently asked questions
What is good cash flow for a rental property?
Most investors want cash flow to stay positive after realistic reserves for vacancy, repairs and replacements, with enough margin to absorb a bad month. The right target depends on your market, financing and goals.
What is the 50% rule?
A rough screening shortcut assumes operating costs consume half of rent. It is not a property forecast. Use itemized local costs and keep capital reserves, debt service and tax separate when comparing ratios.
Why include a capital expenditure reserve?
Roofs, water heaters, HVAC and appliances wear out. Setting aside a share of rent each month spreads those big bills so they do not wipe out a year’s cash flow.
Sources
This tool gives an estimate for general information only. It is not financial, tax, legal or medical advice — check with a qualified professional before you rely on the result.
Last updated: 2026-10-30