- → NOI measures how much income a property generates after operating expenses, before debt, taxes, and depreciation.
- → The formula is: NOI = Gross Operating Income – Operating Expenses
- → Mortgage payments, capital expenditures, depreciation, and income taxes are all excluded from NOI.
- → NOI is the basis for calculating cap rate, implied property value, and the debt service coverage ratio (DSCR).
- → Lenders use NOI to determine whether a property's income is sufficient to support a loan, a negative NOI will typically result in a declined application.
- → You can improve NOI by increasing rents, adding ancillary income streams, and reducing controllable operating expenses.
Net operating income (NOI) is one of the most important numbers in real estate investing. It tells you how much income a property generates after operating expenses are paid, but before debt service, taxes, and depreciation are factored in. If you want to know whether a rental property is worth buying, NOI is where the analysis starts.
Table of Contents
What Is NOI?
Net operating income is a pre-tax metric used to measure the profitability of an income-generating property. It accounts for all revenue the property produces, primarily rent, but also ancillary income such as laundry fees, parking, or storage, and subtracts the costs of running the property day-to-day.
What NOI does not include is equally important. Mortgage payments, loan interest, capital expenditures, depreciation, and income taxes are all excluded. This makes NOI a clean measure of operational performance that is consistent across investors, regardless of how a deal is financed.
In other industries, the equivalent metric is EBIT (earnings before interest and taxes). In real estate, NOI is the standard.
Why NOI Matters
NOI is not just a profitability check. It is the foundation for several other calculations that real estate investors rely on when evaluating deals:
Capitalization rate: Divide NOI by the property’s market value and you get the cap rate, a quick way to compare the return potential of different properties. Use our cap rate calculator to run the numbers.
Property value: Rearrange the cap rate formula and NOI can help you estimate a property’s fair market value. If you know the NOI and the prevailing cap rate in a market, the implied value is NOI divided by cap rate.
Debt service coverage ratio (DSCR): Lenders use this ratio to assess whether a property’s income is sufficient to cover loan repayments. It is calculated by dividing NOI by annual debt service. A DSCR above 1.25 is typically required for a DSCR loan.
The NOI Formula
For a straightforward rental property, this is all you need. But for a more accurate picture that accounts for vacancies and additional income, a more complete version of the formula is useful:
| Component | What it means |
|---|---|
| Potential rental income | Total income if the property were 100% occupied at market rents, year-round. Use comparable listings to estimate if the property is currently vacant. |
| Vacancy loss | Estimated income lost to vacant units, tenant turnover, or non-payment. Benchmark against comparable properties or the property's historical records. |
| Effective rental income | Potential rental income minus vacancy loss. This is the realistic, collectible rent figure. |
| Other income | Any revenue outside of rent — laundry machines, parking charges, storage units, pet fees, or late payment fees. |
| Gross operating income | Effective rental income plus other income. The total revenue the property generates after accounting for vacancy. |
| Operating expenses | All costs required to run the property — property taxes, insurance, maintenance and repairs, property management fees, utilities (if landlord-paid), and accounting costs. Does not include mortgage payments or capital expenditures. |
| Net operating income | Gross operating income minus operating expenses. The final number that tells you whether the property is operationally profitable. |
What is Included and Excluded in NOI?
| Included in NOI | Excluded from NOI |
|---|---|
| Rental income (all units) | Mortgage principal & interest payments |
| Parking, storage, and laundry fees | Income taxes |
| Pet fees and other ancillary income | Depreciation and amortization |
| Property taxes | Capital expenditures (e.g. roof replacement, HVAC) |
| Insurance premiums | Tenant improvement costs |
| Property management fees | Loan origination fees |
| Maintenance and repairs | Investor income tax |
| Utilities (if landlord-paid) | Vacancy loss (deducted before GOI, not from NOI directly) |
How to Calculate NOI: Step-by-Step
Step 1 — Calculate potential rental income Add up all rents across all units at full occupancy, annualized. For a four-unit property at $1,500/month per unit, that is $72,000 per year.
Step 2 — Subtract vacancy loss Use the property’s historical vacancy rate, or comparable properties in the area. At 10% vacancy, that is $7,200 deducted, leaving effective rental income of $64,800.
Step 3 — Add other income If the property has a laundry machine earning $1,000/year, gross operating income becomes $65,800.
Step 4 — Subtract operating expenses If total annual operating expenses are $15,000, the NOI is:
$65,800 – $15,000 = $50,800
NOI Calculation Examples
Example 1: Single-family rental
A single-family rental has a potential rental income of $10,000 per year. Vacancy loss is estimated at $500 (5%). A laundry connection generates another $50 in other income. Total operating expenses (property taxes, insurance, maintenance) come to $3,100.
A small retail unit generates $36,000 in annual rent. Vacancy loss based on local market data is 8% ($2,880). There is no other income. Operating expenses (taxes, insurance, common area maintenance) total $9,500.
The commercial example illustrates that NOI analysis applies equally to residential and commercial assets. The inputs change, but the logic is the same.
Using NOI to Calculate Cap Rate and Property Value
Once you have NOI, you can use it to assess whether an asking price makes sense.
Cap rate formula:
Implied property value:
If comparable properties in the same market trade at a 7% cap rate and your property generates $50,800 in NOI, the implied value is approximately $725,700. This is a useful sanity check when evaluating asking prices or making an offer. Learn more in our guide on how to calculate cap rate.
NOI: What Goes In, What Stays Out
What is a Good NOI?
There is no universal benchmark for a “good” NOI because it depends entirely on the property type, location, and purchase price. A $50,000 NOI on a $400,000 property is a strong result. The same NOI on a $2 million property is less compelling.
The most useful comparison is against similar properties in the same market. If your NOI is significantly lower than comparable assets, it signals either above-average expenses or below-market rents — both of which can often be corrected.
When evaluating deals, always look at NOI relative to the asking price, not in isolation.
How to Improve NOI
Since NOI is a function of income minus expenses, improvements come from either side of the equation.
Increase revenue:
- Push rents to market rate, especially for long-tenured tenants paying below market
- Add or increase ancillary income — parking, storage units, pet fees, laundry
- Reduce vacancy by improving tenant screening, retention, and response times
- Make targeted upgrades (updated kitchens, in-unit laundry) that justify rent increases
Reduce operating expenses:
- Renegotiate insurance and service contracts annually
- Address maintenance proactively to avoid costly emergency repairs
- Implement energy-efficient upgrades to reduce utility spend
- Evaluate whether in-house management is more cost-effective than third-party fees at scale
Even modest improvements on both sides can meaningfully lift NOI. A $200/month rent increase combined with a $100/month reduction in operating expenses adds $3,600 to annual NOI — which, at a 7% cap rate, implies approximately $51,000 in additional property value.
NOI vs. Net Income: What is the Difference?
This is one of the most common points of confusion. Net income accounts for mortgage interest, depreciation, and income taxes, all of which are excluded from NOI. Because those costs vary significantly by investor and financing structure, using net income to compare properties across different owners would produce misleading results.
NOI strips out financing costs so the property’s operational performance can be assessed independently of how it is financed. That consistency is precisely why lenders, appraisers, and investors use it as a standard metric.
In other sectors, EBITDA (earnings before interest, taxes, depreciation, and amortization) serves the same purpose — a clean measure of operating performance before capital structure decisions cloud the picture.
Common Mistakes When Calculating NOI
Using gross rents instead of effective rents. Always factor in vacancy. Using 100% occupancy in your projections inflates NOI and leads to overpaying.
Forgetting management fees. Even if you self-manage, include a management fee in your expense estimate. If you ever hand the property off or sell it, buyers will apply it in their own analysis.
Confusing capital expenditures with operating expenses. Replacing a water heater is a repair. Replacing the entire roof is a capital expenditure. CapEx is excluded from NOI. Including it in operating expenses distorts the metric and understates profitability.
Not adjusting for one-time items. If operating expenses in a given year were unusually high due to a single large repair, normalize the figure before using it in your NOI calculation.
Calculate Your NOI
Use our calculator to quickly work out the net operating income for any rental property. If you are also evaluating financing, our DSCR loan calculator will show you how NOI feeds into your debt coverage ratio.
FAQ
NOI is almost always calculated on an annual basis. All income and expense inputs should be annualized before running the calculation.
No. Mortgage principal and interest are excluded from NOI. They vary by investor and financing structure, so including them would make it impossible to compare properties objectively. To assess loan repayment capacity, use the debt service coverage ratio (NOI ÷ annual debt service).
Yes. Property taxes are an operating expense and are included in the NOI calculation.
Not exactly. Both are pre-tax, pre-interest metrics, but EBITDA is used across industries and also adds back depreciation and amortization. In real estate, NOI is the standard equivalent.
If operating expenses exceed gross operating income, the result is negative. This is called a net operating loss (NOL) and is a strong signal that a property is not financially viable at current rents or expense levels — or that the purchase price is too high.
Yes. A property with high vacancy, below-market rents, or excessive operating costs can produce a negative NOI. Lenders will typically decline to finance a property showing a net operating loss.
The bottom line
NOI is the starting point for almost every serious real estate investment analysis. It tells you whether a property generates enough income to be worth owning, helps you estimate value, and determines whether financing is viable. Getting it right — using realistic vacancy assumptions, accurate expense figures, and market-rate rents — is what separates a credible underwrite from an optimistic guess.
If you are financing an investment property, New Silver offers fix and flip loans, rental loans, and DSCR loans designed for real estate investors. Our team can help you structure a deal from the numbers up.
