Cap Rate Explained: how investors actually compare real estate deals
Cap rate is the most-cited number in commercial real estate — and the most misused. Here's what it means, the formula, what counts as a "good" rate by asset class and market, and when to ignore it.
The formula
Cap Rate = NOI ÷ Property Value × 100
NOI = annual rental income − operating expenses. Operating expenses include property tax, insurance, maintenance, property management fees, vacancy allowance, and HOA. NOI excludes mortgage payments and capital expenditures (CapEx).
Example: A 4-unit building generates $84,000/year in rent. Operating expenses run $26,000/year. NOI = $58,000. The building is listed at $725,000.
Cap Rate = $58,000 ÷ $725,000 = 8.0%
Why cap rate matters
Cap rate is a financing-neutral way to compare two properties. It treats every deal as if you bought it all-cash — so you're comparing the underlying property's ability to generate income, not the cleverness of your loan.
This makes it useful for:
- Comparing multiple properties in the same market
- Comparing markets (Phoenix vs Cincinnati vs Boston)
- Sanity-checking an asking price against income
- Estimating market value of a property given its NOI
What's a good cap rate? (2025 market norms)
There is no single "good" number — it depends entirely on asset class and market.
| Asset class | Typical 2025 range | Notes |
|---|---|---|
| Class A multi-family (major metro) | 4–6% | Low risk, strong appreciation potential |
| Class B/C multi-family | 6–9% | Higher tenant risk, more deferred maintenance |
| Single-family rental | 5–8% | Hard to scale; appreciation-driven in HCOL markets |
| Suburban office | 7–10% | Post-COVID; vacancy risk elevated |
| Retail (single-tenant NNN) | 5–7% | Triple-net lease shifts opex to tenant |
| Retail (multi-tenant strip) | 6–9% | Higher management overhead |
| Industrial / warehouse | 5–7% | Hot category 2020-2024; some compression now |
| Self-storage | 5–7% | Operationally intensive |
By market: cap rate compression
Cap rates "compress" (go lower) in expensive, high-appreciation markets. Investors accept lower current yields because they expect strong appreciation and low vacancy.
- Tier 1 (SF, NYC, LA, Boston, Seattle): Multi-family cap rates often 4–5% — you're buying for appreciation, not yield
- Tier 2 (Austin, Nashville, Charlotte, Denver): 5–7% typical
- Tier 3 (Cincinnati, Memphis, Birmingham, Cleveland): 7–10% — yield-driven; less appreciation
Cap rate vs cash-on-cash return
These two are often confused. They measure different things:
- Cap rate ignores financing. It's a property metric.
- Cash-on-cash return includes the mortgage. It's a deal metric — it depends on your specific loan.
Example: Same $725K building with 8% cap rate ($58K NOI). With 25% down ($181K) and a $544K loan at 7% (30-year), annual debt service is ~$43,400. After-debt cash flow = $58K − $43.4K = $14.6K/year. Cash-on-cash = $14.6K ÷ $181K = 8.1%.
Cap rate and cash-on-cash happen to be similar here. That's usually a coincidence. With cheaper financing or a larger down payment, cash-on-cash diverges from cap rate significantly.
How to use cap rate to estimate value
Flip the formula: Property Value = NOI ÷ Cap Rate
If the local market cap rate for class B multi-family is 7.5% and a property has a verified NOI of $90,000:
Estimated value = $90,000 ÷ 0.075 = $1,200,000
This is the appraisal's "income approach." Useful as a sanity check against what the seller is asking.
When cap rate misleads
- NOI is not standardized. Sellers exclude expenses (vacancy, management, capex reserves) to inflate NOI and lower the apparent cap rate. Always recalculate NOI yourself.
- Pro-forma vs trailing 12-month. Pro-forma cap rates assume future improvements that may not happen. Trailing actuals are honest. Always ask which one you're looking at.
- Single-family residential. Cap rate is less meaningful for SFR — most value comes from appreciation, not yield. Use cash-on-cash and total-return metrics instead.
- Properties needing significant rehab. Cap rate ignores capex. A 10% cap rate on a building needing $200K of roof/HVAC work isn't actually a 10% return.
- Below-market rents. A 6% cap rate on a building with rents 30% below market may actually be a 9% cap deal once rents are stabilized. Conversely, fully-stabilized rents leave no upside.
Run the numbers on your deal
- Cap Rate Calculator — NOI calculation with itemized expenses + cap rate
- Cash-on-Cash Calculator — Year-1 return after debt service
- Investment Property Calculator — Total year-1 return: cash flow + paydown + appreciation + tax benefit
- BRRRR Calculator — For value-add scenarios where you force NOI growth
Quick rules of thumb
- Cap rate higher than 10% → investigate why the market thinks this property is risky
- Cap rate lower than the 10-year Treasury → you're betting entirely on appreciation
- Cap rate similar to mortgage rate → you may have negative leverage (borrowing makes returns worse, not better)
- Cap rate well above mortgage rate → positive leverage; financing improves returns
Calculate cap rate on a specific property →
NOI calculation with itemized operating expenses (tax, insurance, repairs, management, vacancy, capex reserves) and cap rate output.