Cap Rate vs. Cash-on-Cash Return: Formula and Example

Cap rate measures a rental property's annual net operating income relative to its price or value, before mortgage financing. Cash-on-cash return measures annual pre-tax cash flow relative to the cash invested in the deal. Cap rate helps compare property operations; cash-on-cash return shows how a particular financing plan affects the current cash yield.

The same property can therefore have one cap rate and several possible cash-on-cash returns. Changing the down payment, loan rate, term, closing costs, or initial rehabilitation budget does not change the property's NOI, but it can change both annual cash flow and the amount of cash invested.

Cap rate versus cash-on-cash return at a glance

Neither metric is a complete investment return. Both omit some combination of appreciation, selling costs, income taxes, principal paydown, future capital needs, and the timing of cash flows.

Cap rate formula

Use:

Cap Rate = Annual Net Operating Income / Property Price or Value

Net operating income, or NOI, is effective rental income minus the operating expenses included in the analysis. Mortgage principal and interest are excluded. The federal banking agencies describe direct capitalization as relating a property's value to the net operating income it generates in their commercial real estate valuation guidance.

The denominator needs a clear label. Use acquisition price when analyzing a proposed purchase. Use a supportable current value when evaluating an existing property. Do not switch between price and value when comparing deals without noting the change.

Cash-on-cash return formula

Use:

Cash-on-Cash Return = Annual Pre-Tax Cash Flow / Total Cash Invested

For this site's calculator:

Annual Cash Flow = (Monthly NOI - Monthly Principal and Interest) x 12

Cash Invested = Down Payment + Closing Costs + Initial Rehabilitation

Other analyses may define cash invested differently. Some include loan fees, prepaid items, immediate reserves, or furnishing costs. A comparison is only meaningful when each deal uses the same definition.

Worked example: one property, two return metrics

Assume a rental has a $300,000 purchase price and $2,600 of scheduled monthly rent.

Monthly underwriting assumptions:

• vacancy allowance: $130
• property taxes: $300
• insurance: $150
• repairs and maintenance reserve: $130
• capital expenditure reserve: $130
• property management: $208
• other recurring expenses: $50

Total monthly deductions before the mortgage are $1,098. Monthly NOI is:

$2,600 - $1,098 = $1,502

Annual NOI is:

$1,502 x 12 = $18,024

The cap rate based on the $300,000 purchase price is:

$18,024 / $300,000 = 6.01%

Rounded to one decimal place, the property has a 6.0% cap rate under these assumptions.

Financing plan A: more cash invested

Assume the first financing plan produces:

• monthly principal and interest: $1,100
• down payment, closing costs, and initial work: $90,000

Monthly cash flow is:

$1,502 NOI - $1,100 debt service = $402

Annual cash flow is:

$402 x 12 = $4,824

Cash-on-cash return is:

$4,824 / $90,000 = 5.36%

Financing plan B: less cash invested and higher debt service

Assume a smaller down payment reduces total cash invested to $60,000 but increases monthly principal and interest to $1,300.

Monthly cash flow is:

$1,502 NOI - $1,300 debt service = $202

Annual cash flow is:

$202 x 12 = $2,424

Cash-on-cash return is:

$2,424 / $60,000 = 4.04%

Side-by-side result

The cap rate stays at 6.01% because the property's price, rent, and operating assumptions did not change. The cash-on-cash return falls under plan B because the smaller cash investment is more than offset by higher debt service and lower annual cash flow.

This does not prove that plan A is better. Plan B preserves $30,000 of liquidity that could remain in reserves or be used elsewhere. Loan terms, risk, future refinancing options, and household cash needs still matter.

Why expense definitions can change the answer

Cap rates are only comparable when NOI is calculated consistently. One listing may omit management, vacancy, or replacement reserves while another includes them. That can make the first property's advertised cap rate look higher without making the property economically stronger.

The Rental Wealth Simulator calculator includes entered vacancy, repairs, capital reserves, management, taxes, insurance, HOA dues, and other recurring costs in its planning NOI. Some appraisal or brokerage conventions treat capital reserves separately. The important practice is to disclose the convention and use it consistently.

Use the rental property operating expenses checklist before comparing cap rates. The guide to NOI vs. cash flow explains why debt service is excluded from NOI but included in cash flow.

When cap rate is more useful

Cap rate is useful when you want to:

• compare properties before choosing a financing structure
• isolate operating performance from leverage
• identify whether rent or expenses drive the result
• compare a purchase price with the income it is expected to produce
• run a quick value sensitivity using a supportable market cap rate

A cap rate is not a forecast of total return. It does not show how much cash is required, whether the property has positive cash flow after the mortgage, or whether appreciation will occur.

When cash-on-cash return is more useful

Cash-on-cash return is useful when you want to:

• compare different down payments or loan terms
• estimate the current pre-tax yield on invested cash
• see how closing costs or initial work affect the first-year result
• compare a leveraged rental with another use of the same cash
• test whether higher debt service leaves an adequate monthly cushion

Cash-on-cash return can look unusually high when very little cash is invested. That may reflect leverage rather than strong property operations. Review the dollar cash flow, DSCR, reserves, and downside scenario alongside the percentage.

Should you choose the property with the higher percentage?

Not automatically. A higher cap rate may accompany greater vacancy, repair, location, tenant, or resale risk. A higher cash-on-cash return may depend on aggressive leverage, understated expenses, or a thin cash reserve.

Use the same definitions and a realistic downside case. Then evaluate:

• monthly cash flow in dollars
• cash retained after closing
• debt service coverage
• expected repairs and replacements
• tenant and market concentration
• loan maturity and rate risk
• holding period and likely selling costs

The best choice is the one whose expected return and risk fit the household's complete plan, not simply the highest isolated percentage.

Calculate both metrics with the same assumptions

Enter the purchase price, rent, operating expenses, loan terms, closing costs, and initial work in the Rental Cash Flow Calculator. It calculates NOI, cap rate, monthly cash flow, cash-on-cash return, and DSCR from one consistent set of assumptions.

Review the exact definitions on the calculator methodology page, then use the Rental Property Wealth Simulator to test how cash flow, debt paydown, and equity could affect the longer-term portfolio.