Net Operating Income (NOI) Calculator

Calculate Net Operating Income (NOI) — revenue minus operating expenses (before debt service). Core commercial underwriting metric for evaluating property performance and calculating cap rate.

Rental Income

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Total monthly rent collected from all units

— OR —

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Total annual rent for all units

Operating Expenses

Enter either monthly or annual amounts for each expense category. Operating expenses do NOT include mortgage/debt service.

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$
$
$
Routine maintenance, repairs, and reserves
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Typically 8-10% of rent if using a property manager
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Only if paid by landlord (water, sewer, trash, etc.)
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Landscaping, snow removal, pest control, legal, etc.

Understanding Net Operating Income (NOI)

What is NOI?

Net Operating Income (NOI) is a fundamental metric in commercial real estate and property investment analysis. It represents the annual income generated by a property after deducting all operating expenses, but before deducting debt service (mortgage payments), depreciation, income taxes, and capital expenditures.

Formula: NOI = Gross Rental Income − Operating Expenses

What's Included in Operating Expenses?

Operating expenses include all costs necessary to operate and maintain the property:

  • Property Taxes: Annual property tax bill
  • Insurance: Property and liability insurance
  • Maintenance & Repairs: Routine maintenance, repairs, and reserves
  • Property Management: Property management fees (typically 8-10% of rent)
  • Utilities: Water, sewer, trash, gas, electric (if paid by landlord)
  • HOA Fees: Homeowners association or condo fees
  • Other: Landscaping, snow removal, pest control, legal fees, accounting

What's NOT Included in NOI?

NOI intentionally excludes certain items to provide a pure measure of property operating performance:

  • Mortgage/Debt Service: Principal and interest payments
  • Depreciation: Non-cash accounting expense
  • Income Taxes: Personal or corporate income tax
  • Capital Expenditures: Major improvements like new roof, HVAC replacement

By excluding financing costs, NOI allows investors to compare properties objectively, regardless of how they're financed.

Why NOI Matters

NOI is the foundation of several key real estate metrics:

  • Cap Rate (Capitalization Rate): NOI ÷ Property Value. Measures return independent of financing.
  • Debt Service Coverage Ratio (DSCR): NOI ÷ Annual Debt Service. Measures ability to cover mortgage payments.
  • Property Valuation: Commercial properties are often valued using: Property Value = NOI ÷ Cap Rate

NOI vs. Cash Flow

It's important to distinguish between NOI and cash flow:

  • NOI: Operating income before debt service. Used for property valuation and comparison.
  • Cash Flow: NOI minus debt service (mortgage payments). Actual cash you receive or pay.

A property can have positive NOI but negative cash flow if the mortgage payment exceeds the NOI. Conversely, a debt-free property's cash flow equals its NOI.

Industry Standards

Commercial Real Estate: NOI is the primary metric for underwriting and valuation. Lenders, appraisers, and investors rely heavily on NOI to assess property performance.

Residential Investment: While less formal than commercial, NOI is still valuable for evaluating multi-family properties, comparing investment opportunities, and calculating cap rates.

Important Considerations

  • Vacancy: This calculator assumes full occupancy. In practice, reduce rental income by 5-10% to account for vacancy and collection losses.
  • Stabilized NOI: Underwriters often use "stabilized NOI" which assumes normalized occupancy and market-rate rents, not current conditions.
  • Pro Forma NOI: Forward-looking NOI based on projected rents and expenses after improvements or repositioning.
  • Historical NOI: Actual NOI from prior years, useful for establishing trends and benchmarking.

Using NOI for Valuation

NOI is central to the "income approach" to property valuation:

Property Value = NOI ÷ Cap Rate

For example, if a property generates $50,000 in NOI and comparable properties trade at a 6% cap rate, the estimated value would be: $50,000 ÷ 0.06 = $833,333.

Conversely, if you know the purchase price, you can calculate the going-in cap rate: Cap Rate = NOI ÷ Purchase Price.

Disclaimer: This calculator provides estimates for analysis purposes only and should not be considered financial, investment, or tax advice. Actual property performance may vary significantly based on market conditions, vacancy rates, and unforeseen expenses. Always conduct thorough due diligence and consult with qualified professionals before making investment decisions.