Rental Portfolio Cash Flow Tracker

Aggregate monthly cash flow, annual net and gross yield across a small rental portfolio you can save and revisit.

Rental Portfolio Cash Flow Tracker calculator — free online tool
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What does the undefined do?

It aggregates monthly net cash flow across several rental properties and shows annual net and gross yield, with a save and revisit option.

  • Inputs: the number of properties, average value, average rent, average costs and the mortgage per property.
  • Output: monthly net cash flow, annual net and gross yield.
  • Method: total rent minus operating costs and mortgages, with yield from annual rent over total value.

Quick answer

Three properties valued at 200,000 each, renting for 1,500 with 400 of costs and 800 of mortgage, give 900 a month net and a 9 percent gross yield.

What This Calculator Really Does

A single rental property is easy to track in your head; a small portfolio is not. This tool aggregates the whole set so the monthly cash flow is a single, honest number you can act on. It multiplies the properties by average rent for income, by average monthly costs for operating expenses, and adds the mortgages, then nets them off. Annual net is twelve times the monthly figure, and gross yield is annual rent divided by total property value. The gross yield ignores the mortgage, which is why it looks higher than a real return on your own equity. Use the portfolio store to save each property as a record and revisit it later, so the tracker becomes a living list rather than a one-off sum. Real portfolios vary widely between properties, so treat the averages as a starting view and refine each entry as you save them.

The formula it uses

Monthly net = properties x (rent minus costs minus mortgage). Annual net = 12 x monthly net. Gross yield = annual rent / (properties x value) x 100.

Worked example with real numbers

Three properties at 200,000 each with 1,500 rent, 400 costs and 800 mortgage give 4,500 rent, 1,200 costs and 2,400 mortgage, so the monthly net is 900, the annual net is 10,800 and the gross yield is 9 percent.

Common mistakes to avoid

Assumptions and limitations

The model uses averages across the portfolio, with regular costs and mortgages only. Vacancy, large repairs, capital expenditure, tax and transaction costs are not included.

Disclaimer

This is an educational planning tool, not financial or tax advice. Rental returns, costs and tax treatment vary by market and property, so verify the figures and take professional advice where needed.

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Frequently Asked Questions

How is the undefined calculated?

Rent, costs and mortgages are totalled across the portfolio and netted off; annual net multiplies by twelve and gross yield divides annual rent by total value. The steps panel shows each part.

What do I need to use the undefined?

The number of properties, average value, average rent, average monthly costs and the mortgage per property.

What does the result from the undefined show?

Monthly net cash flow, annual net and gross yield across the portfolio, with the option to save each property and revisit.

What is a good gross yield on a rental?

It varies by market, but many investors look for a gross yield in the region of five to ten percent. Subtract costs and mortgage to find the real cash flow.

Why does gross yield differ from my return?

Gross yield uses rent over value and ignores the mortgage, vacancies and costs. Your return on equity is usually much lower, and cash flow can even be negative.

Is the undefined really free?

Yes — 100 percent free, no sign-up, and everything runs in your browser.

About this page: Built on standard financial formulas (the same conventions banks use), hand-checked against worked examples and covered by automated tests on every build. Maintained by CalcProMaster's developer — not a licensed financial advisor — so results are math education, not financial advice. Read our editorial policy for how content is written and verified. Last reviewed: 2026-10-04
Methodology: Standard financial formulas — amortisation, compound interest, present and future value, tax brackets — using the same conventions banks and tax authorities publish. Rates and thresholds are clearly labelled and dated.
⚠️ Financial Disclaimer: This calculator provides estimates for informational and educational purposes only and does not constitute financial, investment, tax, or legal advice. Consult a qualified financial advisor before making financial decisions.

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