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NOI

Net operating income

Net operating income is what a property earns after vacancy and operating expenses but before any mortgage payment, depreciation or income tax. It describes the building, not the buyer. Two investors bidding on the same duplex compute the same NOI even though one pays cash and the other borrows 80%, which is exactly why every valuation metric is built on it.

NOI = effective gross income − operating expenses

Worked example

The standard deal collects $31,065 after a 5% vacancy allowance and spends $11,755 running the building, so NOI is $19,310.

Every example in this glossary uses the same deal: a $265,000 duplex renting for $2,650 a month, bought with 25% down at 6.75% over 30 years, producing $19,310 of net operating income.

The mistake to avoid

Subtracting the mortgage payment. Debt service is a financing decision; putting it inside NOI makes cap rate depend on the buyer's loan and destroys the comparison the metric exists to make.

Where this is calculated

The noi calculator computes this from your own numbers and shows the arithmetic expanded. Net operating income built line by line from gross scheduled rent, and why the mortgage never appears in it.

Related terms

Back to the full glossary 20 terms with formulas and worked examples.