Cap Rate vs Cash-on-Cash: What Each Really Measures

What they measure

Cap rate (capitalization rate) and cash-on-cash (CoC) look similar but answer different questions.

• Cap rate = Net Operating Income (NOI) ÷ Purchase Price. It measures the property’s unlevered yield — what the building returns as if you bought it all-cash.
• Cash-on-cash = Annual pre-tax cash flow ÷ Total cash invested. It measures the annual cash yield to you after financing and actual cash outlay.

Use cap rate to compare properties or markets on a like-for-like, unlevered basis. Use cash-on-cash to understand the return on your equity given your financing and initial costs.

What cap rate does NOT show

• Financing terms or down payment size
• Immediate repairs or capital expenditures that sit off the NOI
• How much cash you need up-front
• Tax effects, principal paydown, or appreciation

What cash-on-cash does NOT show

• Long-term total return from appreciation or principal paydown
• Tax benefits or depreciation
• The intrinsic operating efficiency of a property independent of leverage

Two worked examples (real numbers)

Example A — a straightforward cash/finance comparison:

Say a duplex lists at $320,000.

1. Gross rents: $3,000/month = $36,000/year
2. Vacancy (5%): -$1,800 => Effective gross income = $34,200
3. Operating expenses (30% of EGI): -$10,260 => NOI = $23,940
4. Cap rate = $23,940 ÷ $320,000 = 7.48%

Financing: 25% down ($80,000), loan = $240,000 at 4.5% 30-year (monthly payment ≈ $1,216.13; annual debt service ≈ $14,594).

1. Annual pre-tax cash flow = NOI - debt service = $23,940 - $14,594 = $9,346
2. Initial cash invested = down payment $80,000 + closing costs (assume 3% of price = $9,600) = $89,600
3. Cash-on-cash = $9,346 ÷ $89,600 = 10.4%

Interpretation: A 7.5% cap rate and a 10.4% CoC are both decent; cap rate shows the property’s operating return, CoC shows the investor’s cash yield after financing and up-front cash.

Example B — a great-looking cap rate that hides required repairs:

A small building lists at $200,000 with reported gross rents $1,500/month = $18,000/year. Seller reports low expenses (10%), so NOI = $16,200.

• Cap rate = $16,200 ÷ $200,000 = 8.1% — looks attractive on paper.

But inspection reveals immediate repairs of $45,000 (roof/plumbing). Financing scenario: 75% LTV (down = $50,000), loan = $150,000 at 5% 30-year (annual debt service ≈ $9,662). Closing costs = $6,000.

• Total cash invested now = down $50,000 + closing $6,000 + repairs $45,000 = $101,000
• Annual pre-tax cash flow = NOI - debt service = $16,200 - $9,662 = $6,538
• Cash-on-cash = $6,538 ÷ $101,000 = 6.5%

So a cap rate of 8.1% translated to only a 6.5% cash-on-cash return once you account for required repairs and the actual cash you must put in.

A high cap rate can be caused by deferred maintenance (low reported expenses) or pricing reflecting immediate capex. Cap rate alone won't reveal the true cash burden.

When to use which

• Use cap rate when: comparing market-level returns, valuing income properties on an all-cash basis, or screening large lists quickly.
• Use cash-on-cash when: assessing a deal you will finance, checking whether the property meets your required cash yield, or deciding between financing structures.

Practical rule: start with cap rate for market comparison, then always run cash-on-cash using the actual loan terms and all upfront costs before making an offer.

Quick deal-underwriting checklist

1. Normalize NOI: add back abnormal items and include a realistic vacancy, management, and reserves line.
2. Add immediate capex to your initial equity, not buried in vague expense items.
3. Compute cap rate (NOI ÷ price) to compare value vs market comps.
4. Compute cash-on-cash with your actual down payment, closing costs, and rehabilitation costs.
5. Stress-test: raise vacancy by 2–5 points and increase interest rate by 1–2% to see sensitivity.
6. Consider the exit: ARV, rehab timeline, and rent-up assumptions (if applicable).

If you want to avoid manual mistakes, run the financing and cash-flow scenarios in a calculator — use the rental cash flow calculator to test multiple financing and repair scenarios quickly.

Bottom line

Cap rate tells you the building’s unlevered income return; cash-on-cash tells you what that building will return to your wallet after financing and upfront cash. A “great” cap rate can still be a bad deal if it hides deferred maintenance, unrealistic expense assumptions, or financing terms that eat your cash flow. Run both metrics, add realistic reserves and repairs, and stress-test financing before you write an offer.

Run the numbers yourself and decide which metric matters most for your strategy.