π’ Net Operating Income Calculator
The property\'s earnings before financing and taxes.
Net operating income
Estimates for planning only, not financial advice.
Net operating income is the profit a property generates from operations alone: rental income minus vacancy losses and operating expenses, with mortgage payments, income taxes, and depreciation left out. It is the number every commercial valuation starts from, because it measures the building, not the buyer's financing. Two investors can pay different prices and borrow differently, but the NOI is the same property either way.
How to Use This Calculator
Enter the gross rental income the property would earn fully occupied, plus other income like parking, laundry, or storage fees. Set a vacancy rate to reflect empty units and unpaid rent. Then enter operating expenses: property tax, insurance, maintenance, management fees, utilities the owner pays, and reserves. Do not include the mortgage, which is a financing choice, not a property trait.
Add rental income and other income to get gross potential income, the ceiling if every unit paid full rent all year.
Apply the vacancy rate to reach effective gross income, the realistic revenue after empty units and collection losses.
Subtract operating expenses to get NOI. Divide NOI by the purchase price to get the cap rate, which our rental property calculator computes alongside cash flow.
The NOI Formula
The formula deliberately excludes debt service, income taxes, depreciation, and capital expenditures. That is what makes NOI comparable across properties and owners: it isolates the real estate from the capital structure. A buyer then layers their own mortgage on top to get cash flow, which is a personal number, while NOI stays a property number.
Worked Example
An eight-unit building brings $240,000 a year in rent plus $12,000 from parking and laundry. Gross potential income is $252,000. At a 5 percent vacancy rate, $12,600 is lost, leaving effective gross income of $239,400. Operating expenses run $80,000 for taxes, insurance, management, and repairs. NOI is $239,400 minus $80,000, which is $159,400 a year, or about $13,283 a month before any mortgage payment.
Reading Your Result
Higher NOI at the same price means a better deal, full stop. But compare carefully: a seller's NOI often uses optimistic vacancy and light maintenance reserves. Underwrite with your own numbers, especially a maintenance reserve of $500 to $1,000 per unit per year that many pro formas quietly omit.
My rule: never let a mortgage sneak into NOI. The moment debt service enters, you are measuring your financing, not the building, and you can no longer compare two properties honestly. Price the property on NOI and cap rate first, then decide what loan it can carry. For the monthly payment math once you have a loan quote, our mortgage payment calculator handles the P and I side.
Estimates for planning only, not financial advice.
Frequently Asked Questions
What is net operating income (NOI)?
Net operating income is a property's annual profit from operations: rental and other income minus vacancy losses and operating expenses. It excludes mortgage payments, income taxes, depreciation, and capital expenditures, so it measures the building itself rather than the owner's financing choices.
How is NOI different from cash flow?
NOI is before debt service; cash flow is after it. Subtract the mortgage payments (and set aside capital reserves) from NOI to get the cash that actually lands in your pocket. Two buyers of the same building share one NOI but have different cash flows because their loans differ.
What is a good NOI?
There is no absolute good number; NOI is judged relative to price through the cap rate (NOI divided by price). A $159,400 NOI on a $2 million building is a 7.97 percent cap rate, solid for many markets. Compare cap rates for similar buildings in the same area, not NOI dollars across different cities.
Does NOI include property taxes and insurance?
Yes. Property taxes, insurance, maintenance, property management fees, utilities paid by the owner, and operating reserves all count as operating expenses and reduce NOI. What stays out: mortgage principal and interest, income taxes, depreciation, and major capital improvements. Capital expenditures are the classic trap: replacing a roof is capex, patching it is maintenance, and only the latter hits NOI.
Why do sellers sometimes inflate NOI?
Because price follows NOI divided by the cap rate, every extra dollar of stated NOI supports a higher asking price. Common tricks: understating vacancy, omitting management fees for self-managed buildings, and skipping maintenance reserves. Always rebuild NOI with your own conservative inputs.
How does NOI relate to property valuation?
In the income approach to valuation, value equals NOI divided by the cap rate. A building with $159,400 of NOI in a market where investors accept a 7 percent cap rate is worth about $2.28 million. Raise the NOI by $10,000 and the value rises by roughly $143,000 at the same cap rate.
Should I include future rent increases in NOI?
For valuing a purchase, use current in-place NOI, then model growth separately. Baking hoped-for rent hikes into today's NOI overstates what the property earns now. Lenders underwrite on current or trailing NOI for the same reason. Build a separate pro-forma for the growth story and discount it for execution risk instead.
What vacancy rate should I assume?
Use the market rate for the property type and area, typically 3 to 8 percent for residential and higher for office or retail. Check local data rather than accepting the seller's number. A building running 95 percent occupied in a 90 percent market will likely revert toward the market over time.
Does NOI include the cost of a property manager?
It should, even if you plan to self-manage. Management typically costs 8 to 12 percent of collected rent. Excluding it flatters the NOI and makes the property look cheaper than it is for any future buyer who will pay for management.
Can NOI be negative?
Yes, when operating expenses and vacancy exceed income, common with heavy renovations, lease-up phases, or distressed buildings. A negative NOI means the property consumes cash before any mortgage is paid. Value it on stabilized future NOI or on comparable sales instead, never on a negative number.