Cash-on-cash return formula: how to calculate CoC

The short answer

Cash-on-cash return measures the first-year pre-tax cash flow a property produces relative to the cash you put into it.

Cash-on-cash return = annual pre-tax cash flow ÷ cash invested × 100

The numerator is a cash number. It is not net operating income. It is what remains after the mortgage is paid.

The denominator is the equity check you write to acquire and stabilize the property. It is not the purchase price, and it is not always just the down payment.

That is the whole formula. The difficulty is in the conventions: what counts as cash flow, what counts as cash invested, and whether the result is being compared with another deal that uses the same definitions.

Step 1: Calculate annual pre-tax cash flow

Start with net operating income (NOI), then subtract annual debt service.

NOI = effective gross income − operating expenses

Annual cash flow = NOI − annual debt service

NOI includes rental income and other property income, minus vacancy and credit loss, minus ordinary operating expenses such as taxes, insurance, management, maintenance, repairs, HOA dues, utilities, and a reserve if you choose to include one.

NOI does not include mortgage principal and interest, income taxes, depreciation, or capital improvements. Those are financing, tax, or capital items.

Annual debt service is the full twelve months of principal and interest, plus any mortgage insurance premium that is part of the payment. Principal is included in debt service even though it is not an operating expense. That is why cash flow is lower than NOI.

Monthly cash flow = annual cash flow ÷ 12

Use monthly cash flow for budgeting. Use annual cash flow for cash-on-cash return.

Step 2: Define cash invested

The denominator is where most cash-on-cash comparisons go wrong.

A conservative all-in definition includes:

• Down payment
• Closing costs
• Immediate rehab or make-ready costs
• Lender fees and origination costs
• Other upfront cash required to close or stabilize the property

For an all-cash purchase, the down payment is the full purchase price. Cash invested is the purchase price plus closing costs, rehab, and other upfront cash.

Some investors use a narrower definition: down payment only. That produces a higher cash-on-cash return because the denominator is smaller. It can be useful for comparing loan structures, but it overstates the return on the total cash required to do the deal.

The important rule is consistency. If you compare a deal that includes closing costs with one that excludes them, you are not comparing the same thing. Pick one convention, disclose it, and use it across the deals you are screening.

Step 3: Divide and express as a percentage

If annual cash flow is $5,677 and all-in cash invested is $56,000:

$5,677 ÷ $56,000 × 100 = 10.14%

That is the all-in cash-on-cash return.

Using the same cash flow and a $50,000 down payment only:

$5,677 ÷ $50,000 × 100 = 11.35%

The two results are not contradictory. They answer slightly different questions. The all-in version asks what the total cash investment earns. The down-payment-only version isolates the return on the down payment and ignores the other cash required to close.

A worked example

Consider a $200,000 single-family rental.

Operating assumptions:

• Monthly rent: $2,300
• Other monthly income: $0
• Vacancy: 5%
• Management: 8% of gross scheduled income
• Maintenance: 5% of gross scheduled income
• Capex: 5% of gross scheduled income
• Annual taxes: $2,400
• Annual insurance: $1,200
• HOA, utilities, and other expenses: $0

Operating math:

• Gross scheduled income: $27,600
• Vacancy loss: $1,380
• Effective gross income: $26,220
• Operating expenses: $8,568
• NOI: $17,652

Financing assumptions:

• Purchase price: $200,000
• Down payment: 25% ($50,000)
• Loan amount: $150,000
• Interest rate: 7%
• Term: 30 years
• Monthly principal and interest: about $998
• Annual debt service: about $11,975
• Closing costs: $6,000
• Other upfront cash: $0

Cash flow and return:

• Annual cash flow: $17,652 − $11,975 = $5,677
• All-in cash invested: $50,000 + $6,000 = $56,000
• Cash-on-cash return: $5,677 ÷ $56,000 = 10.14%

The property’s cap rate on purchase price is $17,652 ÷ $200,000 = 8.83%. The cash-on-cash return is higher than the cap rate because the loan constant is below the cap rate. The loan constant is $11,975 ÷ $150,000 = 7.98%. The leverage spread is 8.83% − 7.98% = 0.84 percentage points.

That spread is a screening tool, not a guarantee. The loan amortizes, the rent and expenses change, and the investor still has to fund vacancies, repairs, and capital items that do not appear neatly in a first-year snapshot.

Why leverage changes the answer

Cash-on-cash return is an equity-level metric. It depends on how the property is financed.

When the property’s unleveraged yield is higher than the cost of the debt, leverage can increase the return on equity. When the cost of the debt is higher than the property’s yield, leverage can reduce it.

The loan constant is a useful comparison because it captures the full annual debt service as a percentage of the loan, including principal. It is not the same as the interest rate. A 7% amortizing loan has a loan constant above 7% because the payment includes principal.

Loan constant = annual debt service ÷ loan amount × 100

Leverage spread = cap rate − loan constant

A positive spread means the property’s operating yield is above the cost of the debt. A negative spread means the financing is reducing the property-level cash yield. The cash-on-cash return can still be positive in a negative-spread deal, but the leverage is not helping.

Reverse solves: what rent or price makes the target?

Investors often start with a required cash-on-cash return and work backward.

The rent needed for a target cash-on-cash return solves for the gross scheduled income that covers fixed expenses, debt service, and the target cash flow after vacancy and percentage expenses. It holds the other assumptions constant.

The maximum price at a target cash-on-cash return solves for the purchase price that produces the target at the current rent, expenses, loan terms, down payment, and upfront costs. It is not an appraisal. It is a narrow answer to a narrow question: what price makes these assumptions hit the target?

Both solves are sensitive to the inputs. A small change in vacancy, taxes, insurance, or the interest rate can move the answer by thousands of dollars. Use them to frame a negotiation, not to replace due diligence.

Common mistakes

Using NOI as the numerator. NOI ignores debt service. Cash-on-cash return is a cash flow measure, so the mortgage has to come out.

Forgetting closing costs and rehab. The down payment is not the only cash required to close. Ignoring the rest makes the return look better than the deal.

Counting principal paydown as cash flow. Principal paydown is a real benefit, but it is not cash in your pocket during the year. It belongs in a total return or IRR analysis, not in the cash-on-cash numerator.

Mixing pre-tax and after-tax numbers. Cash-on-cash return is usually pre-tax. If you use after-tax cash flow, say so, and do not compare it with a pre-tax result from another deal.

Comparing different cash-invested conventions. A down-payment-only return and an all-in return are not the same metric. Put them on the same basis before you rank deals.

Treating one year as the whole story. Cash-on-cash return is a first-year snapshot. It does not capture rent growth, expense growth, appreciation, sale costs, or the risk of a major capital event.

When to use cash-on-cash return

Use it when you want to compare financing plans for the same property, size a down payment, or see what your actual cash investment is producing in the first year.

Use it alongside cap rate, not instead of it. Cap rate tells you about the property’s operating yield before financing. Cash-on-cash tells you about the equity return under a specific loan.

For a longer view, project cash flow and cash-on-cash over several years, then stress-test vacancy, rent, expenses, and the interest rate. A deal that looks fine in year one can look very different after a vacancy increase or a tax reassessment.

Bottom line

The cash-on-cash formula is simple: annual pre-tax cash flow divided by cash invested. The quality of the answer depends on the definitions behind it.

Use all-in cash invested for a conservative headline result. Show the down-payment-only return separately if you need it. Include the full debt service in cash flow. Keep the convention consistent across deals.

Then use the result as one input, not a verdict. A good cash-on-cash return with unrealistic expenses is not a good deal. A modest cash-on-cash return with a strong basis, low leverage, and a margin of safety can be a better investment than a high headline number.

Run the numbers on your own deal with the cash-on-cash return calculator, then compare the result with the cap rate and the rental cash flow under the same assumptions.