Two numbers dominate rental-property analysis: cap rate and cash-on-cash return. They sound similar, but they measure completely different things. Cap rate tells you what the property is worth relative to its income, independent of how you finance it. Cash-on-cash tells you how hard your actual invested dollars are working, after the mortgage. Knowing which one to reach for — and when — keeps you from making expensive comparisons between incompatible deals.
Cap rate: the property’s intrinsic yield
Cap rate (capitalization rate) strips out financing entirely and asks: if you owned this property free and clear, what percentage of the purchase price would the income return?
Cap Rate = Net Operating Income ÷ Property Value (or Purchase Price)
Net operating income (NOI) is annual gross rent minus all operating expenses — vacancy, property management, taxes, insurance, maintenance, and CapEx reserves — but before any debt payments. Because mortgage payments never enter the formula, cap rate is the same whether you paid cash or took out a loan. That makes it a pure measure of the asset itself, useful for comparing properties across markets and financing structures.
Cash-on-cash return: the yield on your actual dollars
Cash-on-cash (CoC) return measures what you earn relative to the cash you personally deployed — down payment, closing costs, any upfront repairs — after the debt service is paid.
Cash-on-Cash Return = Annual Pre-Tax Cash Flow ÷ Total Cash Invested
Annual pre-tax cash flow is NOI minus your annual mortgage payments (principal + interest). Because the mortgage is now in the picture, CoC return rises when you use leverage and falls when interest rates rise. Two identical properties can produce very different cash-on-cash returns depending on how they’re financed.
Try it yourself
Run cap rate, cash-on-cash return, and monthly cash flow for any buy-and-hold rental.
Open the Rental ROI Calculator →A worked example side by side
Consider a duplex purchased for $350,000 with 25% down ($87,500) and $4,500 in closing costs — total cash invested of $92,000. The loan is $262,500 at 7.0% for 30 years, which produces a monthly payment of roughly $1,747 ($20,964/year).
- Gross annual rent: $36,000 ($1,500/unit × 2 units × 12 months)
- Vacancy (8%): −$2,880
- Property management (10%): −$3,312
- Taxes, insurance, maintenance, CapEx: −$6,000
- NOI: $23,808
Cap rate: $23,808 ÷ $350,000 = 6.8%
Annual cash flow: $23,808 − $20,964 = $2,844
Cash-on-cash return: $2,844 ÷ $92,000 = 3.1%
The spread between them — 6.8% cap rate but only 3.1% CoC — illustrates the cost of leverage at today’s rates. The property is producing a solid return on its value, but the mortgage consumes most of that income before it reaches your pocket.
Why the gap between them matters
The relationship between cap rate and your loan’s effective interest cost (called the mortgage constant) determines whether leverage helps or hurts:
- Cap rate > mortgage constant: positive leverage — borrowing amplifies your cash-on-cash return above what you’d earn all-cash.
- Cap rate < mortgage constant: negative leverage — the loan drags your CoC below the cap rate, which is what most buyers face when rates are elevated.
- Cap rate = mortgage constant: neutral leverage — debt neither helps nor hurts your annual cash yield.
In the example above the 30-year mortgage constant at 7.0% is roughly 8.0% (annual payments ÷ loan balance), which exceeds the 6.8% cap rate — so leverage is negative and CoC (3.1%) trails the cap rate. If the same loan were at 5.0%, the mortgage constant drops to about 6.4%, falling below the cap rate and pushing CoC above it.
When to use cap rate
- Comparing properties across financing scenarios. Since debt is excluded, you can stack a turnkey rental against a value-add deal or an out-of-state market against a local one without your financing assumptions contaminating the comparison.
- Valuing a property. Commercial appraisers and brokers routinely derive value as NOI ÷ prevailing market cap rate. If a multifamily trades at a 6% cap in your submarket and a property produces $60,000 NOI, the implied value is $1,000,000.
- Tracking market trends. Rising cap rates generally signal declining values (buyers demanding more yield); falling cap rates signal a competitive market with strong appreciation expectations.
When to use cash-on-cash return
- Evaluating whether to buy (with a specific loan). CoC is the number that tells you what the deal actually puts in your pocket every year relative to what you wrote a check for. It’s the lever that answers “does this deal work for me, at this rate, with this down payment?”
- Comparing different financing structures on the same property. A 20% down payment vs. 30% down will produce the same cap rate but very different cash-on-cash returns.
- Setting a minimum hurdle rate. Many investors target 6–10% cash-on-cash as a minimum before they’ll buy. Others accept lower CoC if they expect strong appreciation or tax advantages.
Frequently asked questions
Is a higher cap rate always better?
Not automatically. A high cap rate in a thin market may signal higher vacancy risk, deferred maintenance, or a landlord-unfriendly environment. A low cap rate in a gateway city often reflects stable demand and appreciation potential. Interpret cap rate in context of the specific market and asset class.
Can cash-on-cash return exceed the cap rate?
Yes — when the mortgage constant is below the cap rate, leverage amplifies your yield and CoC rises above it. This was common when 30-year rates were in the 3–4% range.
Does cap rate account for mortgage paydown?
No. Neither cap rate nor cash-on-cash return capture principal paydown, appreciation, or tax benefits. For a complete picture of total return, you need to model those separately — or use a metric like IRR over a projected hold period.
What’s a good cap rate for a rental?
It varies widely by market. Urban coastal markets often trade at 4–5% cap rates; secondary and tertiary markets can see 7–9% or higher. The “good” cap rate is the one that, given local appreciation expectations, total return targets, and risk tolerance, clears your hurdle.
What’s a good cash-on-cash return?
A common investor target is 6–10% pre-tax cash-on-cash, but the right number depends on your alternatives. If a risk-free Treasury yields 5%, a 6% CoC on a leveraged rental with execution risk may not compensate adequately. Many value-add investors accept lower initial CoC in exchange for a clear path to rental growth or forced appreciation.
The bottom line
Use cap rate to evaluate the property; use cash-on-cash to evaluate the deal as you’re structuring it. Cap rate is your apples-to-apples benchmark across markets and financing scenarios; cash-on-cash is your annual report card on the dollars you actually deployed. Neither number alone tells the whole story — the strongest investors track both.
Run the full expense stack and your loan terms through the Rental ROI Calculator to see cap rate, cash-on-cash, and annual cash flow in one view. If you’re financing with a DSCR loan, cross-check the deal in the DSCR Loan Calculator to confirm the property qualifies at the loan amount you need.