Quick answer
Net operating income is a rental property's income after operating expenses are subtracted, but before mortgage payments, income taxes, depreciation, and some financing-related costs. Investors use NOI to evaluate how the property itself performs as an income-producing asset.
A simple formula is gross rental income minus vacancy and operating expenses equals NOI.
What goes into NOI
NOI starts with property income, then subtracts operating expenses. Income may include rent and other property-related income. Expenses may include:
- Property taxes.
- Insurance.
- Repairs and maintenance.
- Property management fees.
- Utilities paid by the owner.
- HOA dues when applicable.
- Lawn care or recurring services.
- Vacancy allowance.
The exact treatment can vary by analysis, so owners should be consistent when comparing properties.
What is usually excluded from NOI
NOI usually excludes mortgage payments, loan principal, interest, depreciation, income taxes, and owner-specific financing decisions. This helps investors compare the property's operations separately from how the owner financed it.
Cash flow and NOI are related, but they are not the same. Cash flow often includes debt service and other owner-specific cash movements.
Why NOI matters
NOI helps owners and investors understand property performance. It can support rent pricing decisions, expense review, portfolio comparisons, and valuation methods such as cap rate analysis.
If NOI is weak, the issue may be low rent, high vacancy, high expenses, repair needs, taxes, insurance, or a combination of factors.
How owners should use NOI carefully
NOI is only as useful as the assumptions behind it. If an owner underestimates repairs, ignores vacancy, or uses unrealistic rent, the NOI estimate may look stronger than the property can actually support.
Owners should separate gross rent, NOI, and cash flow so they understand each layer of rental performance.
Related resources
- Rental Income and Pricing category
- What is rental property cash flow?
- What affects rental income?
- How do vacancy and maintenance affect rental income?
- Rental Revenue Calculator
Frequently asked questions
Is NOI the same as cash flow?
No. NOI usually excludes debt service, while cash flow often includes mortgage payments and other owner-specific costs.
Does NOI include property management fees?
Often, yes. Property management fees are usually treated as operating expenses in rental property analysis.
Does NOI include mortgage payments?
Usually no. Debt service is typically excluded from NOI.
Why does NOI matter to investors?
NOI helps investors evaluate the income performance of the property before financing choices.