What Is Net Operating Income in Commercial Real Estate?

Net operating income, commonly abbreviated as NOI, is a financial measurement used to evaluate the operating performance of income-producing real estate. It represents the income remaining after ordinary property operating expenses are deducted from effective gross income.

NOI is widely used when analyzing office buildings, retail properties, industrial and warehouse properties, multifamily buildings, mixed-use properties and other income-producing commercial real estate.

Because NOI focuses on property operations rather than an individual owner’s financing structure, mortgage principal and interest are generally not deducted when calculating NOI.

How to Calculate Commercial Property NOI

Calculating NOI generally begins with the property’s potential rental income. Vacancy and collection loss are then considered, followed by additional property income and recurring operating expenses.

Step 1: Calculate Gross Potential Income

Gross potential income represents the property’s scheduled income before vacancy and collection loss.

Depending on the property, income may include base rent and other recurring rental income.

Step 2: Account for Vacancy and Collection Loss

A commercial property may not collect every dollar of scheduled rent. Space can become vacant, leases can expire and tenants may occasionally fail to make required payments.

Step 3: Add Other Property Income

Commercial properties may generate income beyond base rent. Depending on the property and leases, this can include tenant expense reimbursements, parking, storage, signage and other recurring income.

Step 4: Calculate Effective Gross Income

Step 5: Subtract Operating Expenses

Recurring expenses necessary to operate the property are deducted from effective gross income to estimate NOI.

Example of a Commercial NOI Calculation

This example is simplified. Actual commercial properties can have multiple tenants, different lease structures, reimbursements, expense caps, vacancies and property-specific operating costs.

What Expenses Are Included in NOI?

Operating expenses generally include recurring costs required to operate and maintain the property.

Depending on the property, these may include property taxes, property insurance, repairs and maintenance, property management, landscaping, snow removal, janitorial services, owner-paid utilities and other recurring operating expenses.

The exact treatment of an expense may vary depending on the property and the purpose of the analysis.

What Is Usually Not Included in NOI?

NOI is designed to measure property-level operating performance rather than the owner’s complete investment return.

Items commonly analyzed separately may include mortgage principal and interest, income taxes, depreciation and certain major capital expenditures.

This distinction is important because two investors could purchase the same property using different financing arrangements while the underlying property’s NOI remains the same.

NOI and NNN Commercial Leases

In a triple-net, or NNN, lease structure, tenants may reimburse the landlord for some or all of the property’s taxes, insurance and common operating expenses.

Those reimbursements can affect the property’s income and expense presentation. When analyzing an actual property, investors should review the leases and financial statements carefully to understand which expenses are paid or reimbursed by tenants.

NOI vs. Cash Flow

NOI and cash flow are related but they are not the same measurement.

NOI measures property operating income before financing. Cash flow generally considers additional obligations such as debt service.

Additional capital expenditures, reserves and other investment-specific costs may also affect actual cash flow.

NOI vs. Cap Rate

NOI is an income measurement, while capitalization rate compares NOI with a property’s value or purchase price.

For example, a property generating $100,000 of annual NOI and valued at $1,250,000 would have an 8% capitalization rate based on those figures.

Using NOI to Estimate Commercial Property Value

When an appropriate market capitalization rate is available, NOI can also be used to estimate an implied property value.

This calculation is not an appraisal. Selecting an appropriate capitalization rate requires consideration of property type, location, tenant quality, leases, condition, market conditions, growth expectations and investment risk.

What Is the Operating Expense Ratio?

The operating expense ratio compares total operating expenses with effective gross income.

The ratio can help investors understand how much of the property’s effective income is being consumed by operating expenses.

What Is NOI Margin?

NOI margin shows the percentage of effective gross income remaining after operating expenses.

There is no single NOI margin that makes every commercial property attractive. Expense structures vary substantially across property types and markets.

Why Accurate NOI Matters

An incorrect NOI calculation can materially affect an investor’s analysis. Overstating income or understating expenses can make a property appear more profitable or valuable than its actual operations support.

When evaluating a commercial property, investors may need to verify rent rolls, leases, historical operating statements, tax records, insurance costs, utility expenses, service contracts and other financial information rather than relying solely on marketing figures.

Commercial Property NOI Calculator FAQs