How this instrument works
A capitalization rate states how much annual income a property throws off relative to what it costs, expressed as a single percentage. The formula is deliberately built around net operating income rather than cash flow to the owner, because NOI is measured before any mortgage payment is subtracted — two buyers financing the same building completely differently would still be looking at the same cap rate, since the metric describes the real estate itself, not the deal structure layered on top of it.
Appraisers use it in the income approach to valuation, landlords use it to sanity-check an asking price against rents already in place, and REIT analysts use it to line up dozens of properties on one scale without pulling every mortgage document first. A downtown apartment building might trade around a 4-5% cap rate because buyers accept a lower yield for a stable, sought-after location, while an older strip mall two counties out might trade at 8-9% because buyers demand more income to accept more risk and less liquidity.
What the number leaves out matters as much as what it includes. It says nothing about debt service, so a highly leveraged buyer's actual cash return can sit far above or below the cap rate. It also omits capital expenditure reserves, closing costs, and any change in the property's value over the holding period — a high cap rate compensates for real risk as often as it signals a bargain, and the figure alone cannot tell you which.
- Enter Net operating income, $/yr — rent actually collected, minus vacancy loss and operating expenses, before any mortgage payment is subtracted.
- Enter Property value, $ — the asking price you are evaluating, or the current appraised value if you already own the building.
- Read Capitalization rate, % — the yield the property would return if it were bought entirely in cash, with no financing involved at all.
- Compare that figure against cap rates on similar buildings in the same submarket to judge whether the price is rich or cheap for the income it produces.
Worked example — a $600,000 fourplex
Take a fourplex listed at $600,000 that generates $45,000 a year in net operating income once vacancy allowance and operating costs are subtracted from the rent it collects. Dividing $45,000 by $600,000 and multiplying by 100 gives a cap rate of 7.5% — the return the property would produce if bought entirely in cash, with no mortgage anywhere in the picture.
That 7.5% figure lets an investor set this fourplex against a duplex across town quoted at a 6% cap rate, or an apartment block quoted at 9%, without needing to know how any of the three deals would be financed. A lower cap rate usually signals a safer, more sought-after building; a higher one usually signals more risk or a more management-heavy asset, and the instrument stops at the arithmetic — it will not tell you which trade-off suits a given buyer.
Questions
What counts as net operating income?
Net operating income is the rent a property actually collects, minus vacancy and credit loss, minus operating expenses such as property tax, insurance, repairs, and management fees. It excludes mortgage payments, income tax, and capital improvements — those sit below NOI, not inside it. Get NOI wrong and the cap rate that follows is wrong too, however carefully the division itself is done.
Why does cap rate ignore the mortgage entirely?
Because it is built to compare properties, not financing packages. Two identical buildings bought with different down payments and interest rates would show very different cash-on-cash returns, but the same cap rate, since the metric measures the income the real estate produces before anyone decides how to pay for it.
What counts as a good cap rate?
There is no fixed good number — it depends on the market and asset type. Core urban apartments often trade around 4-5% because buyers accept a lower yield for stability; older multifamily or retail in a secondary market can run 7-9% or higher because buyers demand more income to accept more risk. Compare a property's cap rate against similar listings nearby, not against a target pulled from elsewhere.
How is cap rate different from cash-on-cash return?
Cap rate divides NOI by the property's value and ignores financing; cash-on-cash return divides annual cash flow after debt service by the cash actually invested, so it reflects the specific loan a buyer used. A leveraged buyer's cash-on-cash return can land well above or below the property's cap rate depending on the loan terms — the two numbers answer different questions and are not interchangeable.
Can this formula be used to price a property instead?
Yes, indirectly — rearranging it so that value equals NOI divided by a market cap rate estimates what a buyer might pay for that income stream, and appraisers use exactly this income approach alongside comparable sales. It only works if the market cap rate chosen is defensible for that asset class and submarket, which is local data this instrument does not supply.
Does a higher cap rate always mean a better deal?
No. A high cap rate often prices in real risk — a weaker location, deferred maintenance, a short remaining lease term, or a tenant more likely to default. This instrument shows what the income and the price produce mathematically; it says nothing about why the market priced the building that way, and that judgment is not one the number can make on its own.
References
- IRS — Residential Rental Property (Publication 527)
- SEC Investor.gov — Real Estate Investment Trusts (REITs)
Read this first: This instrument shows arithmetic, not advice. Real offers add fees, taxes and terms that vary by lender and place — verify the figures against your actual paperwork before deciding anything.