Investment Concepts
Net Operating Income (NOI) in Real Estate: Formula, Examples, and Uses
Net Operating Income (NOI) is the foundational metric for valuing and analyzing income-producing real estate. It tells you how much income a property generates from operations, before financing and taxes. If you work with investors or commercial clients, you must understand NOI cold.
The NOI Formula
NOI = Effective Gross Income (EGI) − Operating Expenses. EGI = Gross Potential Rent − Vacancy and Credit Loss + Other Income (parking, laundry, etc.). Operating expenses include property taxes, insurance, management fees, maintenance, utilities (if landlord pays), and reserves for replacement. Operating expenses do NOT include mortgage payments (debt service), depreciation, income taxes, or capital improvements.
This is the most common point of confusion: NOI is calculated BEFORE debt service. A property's NOI is the same whether it's purchased with cash or 90% leverage — because NOI measures the property's performance, not the investor's financing decision.
NOI Calculation Example
Income
12-unit apartment building. Gross potential rent: $18,000/mo ($216,000/year). Vacancy (5%): −$10,800. Laundry income: +$1,200. Effective Gross Income: $206,400/year.
Operating Expenses
Property taxes: $18,000. Insurance: $6,000. Management (8%): $16,512. Maintenance: $12,000. Utilities (common areas): $4,800. Reserves: $6,000. Total OpEx: $63,312.
NOI
EGI ($206,400) − Operating Expenses ($63,312) = NOI of $143,088/year. This is the income available to service debt and provide return to the investor.
Property Value via Cap Rate
If the market cap rate for this property type is 6%: Value = NOI ÷ Cap Rate = $143,088 ÷ 0.06 = $2,384,800. Increasing NOI (via rent increases or expense reduction) directly increases property value.
NOI FAQ
What is the difference between NOI and cash flow?
NOI is before debt service; cash flow is after. NOI = EGI − Operating Expenses. Cash Flow = NOI − Debt Service (mortgage payments). Two properties with identical NOI can have very different cash flows depending on how much debt they carry.
What is a cap rate and how does it relate to NOI?
Cap Rate = NOI ÷ Property Value. Or rearranged: Property Value = NOI ÷ Cap Rate. If a property has $100,000 NOI and the market cap rate is 5%, the implied value is $2 million. Cap rates are inversely related to value — lower cap rates mean higher prices (more expensive market or more desirable property).
Does mortgage interest affect NOI?
No. NOI is calculated before financing. Mortgage interest is a financing expense that affects cash flow and taxable income, but not NOI. This is intentional — it allows comparison of properties regardless of how they're financed.
How can an investor increase a property's NOI?
Raise rents to market rate (most impactful), reduce vacancy through better tenant screening and retention, add income streams (coin laundry, storage, parking, pet fees), and reduce operating expenses (negotiate insurance, install low-maintenance landscaping, implement energy efficiency improvements).