See your real monthly profit on a rental — after expenses and the mortgage. Enter three numbers to get monthly and annual cash flow.
Cash flow = rent − operating expenses − mortgage payment. Positive cash flow means the property pays for itself each month.
Cash flow is the money left in your pocket each month after every cost. A property can show a strong yield on paper but still be cash-flow negative once the mortgage is included. Positive monthly cash flow is what makes a rental sustainable long term.
Rent comes in at $1,900/month. Monthly expenses (insurance, tax, maintenance reserve, management) total $520, and the mortgage payment is $1,180. Cash flow = $1,900 − $520 − $1,180 = $200/month, or $2,400/year — modest but positive. If a vacancy month or a surprise repair briefly wiped that out, the property would need only a small rent increase (about 3-4%) to rebuild a comfortable buffer, which is why many investors prefer properties with $200-400/month of margin rather than breaking even exactly.
When rent exceeds your expenses plus mortgage, the property generates surplus cash each month — positive cash flow.
Insurance, property management, maintenance reserves, property tax, HOA/service charges, and any utilities you pay. Don't double-count the mortgage.
Reduce vacancy, review expenses annually, refinance if rates drop, or adjust rent within local legal limits — check the rent increase laws page for your country.
RentFlow totals rent and expenses per property so your monthly cash flow updates itself. Free to start.
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