Real Estate & Mortgages
Basic

Net Operating Income

Rental income minus operating expenses.

Formula

NOI=GI−OENOI = GI - OE

Live Calculator

Members

Variables

NOINet operating income
GIGross income
OEOperating expenses

Example

GI=$40k, OE=$14k: NOI = $26k

How it works

Net Operating Income (NOI) shows how much money a property produces from its day-to-day operations after normal operating costs are paid. It is found by subtracting operating expenses from gross income because the result isolates the property’s operating performance before financing costs, taxes, and depreciation are considered. That makes it a useful measure of a property’s earning power on its own.

When to use it

Use NOI when evaluating rental properties, comparing investment properties, or estimating how well a building is performing financially. It is especially helpful in real estate analysis before deciding on a purchase, refinance, or sale.

Worked example, step by step

Given: GI = $72,000 and OE = $29,500 Step 1: Write the formula: NOI = GI - OE Step 2: Substitute the values: NOI = $72,000 - $29,500 Step 3: Subtract: NOI = $42,500 Final answer: NOI = $42,500

Common mistakes to avoid

  • Including mortgage payments in operating expenses
  • Using net income instead of gross income in the formula
  • Forgetting to subtract expenses such as maintenance, insurance, and management costs

Did You Know?

NOI excludes mortgage payments and tax so properties can be compared regardless of how they're financed.

Share this formula

Reviewed & maintained by the FormulaWon editorial teamLast reviewed September 2026