What Is Net Operating Income (NOI) In Real Estate?

What Is Net Operating Income (NOI) In Real Estate?

When I initially come across an acronym, I instinctively think about dentistry. I guess because so many have been ingrained in my brain during my lengthy training I can’t help it.

After starting this blog years ago, I quickly learned that real estate investors, like medical professionals, communicate extensively using acronyms.

When I originally learned about the phrase NOI, my initial thought was that this stands for “Nighttime Oral Irrigator” or “Naso-Oral Infection.” But I was wrong :).

The NOI calculation, or net operating income, is an extremely important concept to understand when evaluating real estate investments.

In this article, we’re going to discuss what it is, the best way to calculate the Net Operating Income formula, and go over an example of using it with an investment property to make you a better real estate investor.

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What Is NOI?

Net Operating Income (NOI) demonstrates the cash flow and profit potential of a rental property. It achieves this by comparing the property’s annual income streams, minus the expenses required for its operation.

The NOI of a property is a strong indicator of its ongoing revenue but does not include deductions for:

  • debt payments
  • taxes
  • depreciation
  • mortgage payments
  • capital expenses (CAPEX)

Because NOI doesn’t take these into account, it’s less susceptible to manipulation based on the amount of leverage used compared to other financial metrics, such as cash-on-cash return.

The net operating income calculation helps when comparing multiple properties. Unlike residential real estate, that’s priced based on comparable properties (Comps) in the area, commercial real estate is based on the NOI.

If I’m trying to decide on which apartment building to purchase, then the one with the higher NOI can help make the decision easier.

NOI Formula

The formula for calculating the property’s NOI is:

Net Operating Income = (Gross Operating Income + Other Income) – Operating Expenses

Let’s walk through some of the numbers to include in the formula, along with how to calculate NOI.

To more accurately calculate NOI, here are some of the different terms:

Potential Rental Income

The total amount of income generated if a property is occupied 100% of the time is the potential rental income. As you might expect, the likelihood of a property being rented out 100% of the time is extremely low.

Vacancy Loss

Vacancy loss is exactly what it sounds like. This is the potential rental income lost due to vacancy.

Vacancies can be caused by:

  • tenant turnover
  • eviction

Many of the real estate syndications I’ve invested in typically use a pro forma vacancy rate equal to 5% of the potential rental income.

Effective Rental Income

Subtracting vacancy loss from potential rental income gives the rental income a landlord can reasonably anticipate receiving.

Potential rental income – vacancy loss = Effective rental income

Other Income

Besides rent, property owners can bring in income from other areas such as:

  • pet fees
  • late fees
  • laundry facilities

Gross Operating Income (GOI)

The GOI is the sum of other income and effective rental income.

Total Operating Expenses

The costs needed to operate the property including:

  • taxes
  • insurance
  • maintenance/repairs
  • property management costs

Understanding Net Operating Income (NOI)

As mentioned, the NOI is calculated by subtracting the property’s operational expenses from its effective gross income. 

Examples of operational costs are:

  • property taxes
  • utilities
  • repairs
  • legal fees
  • ongoing maintenance costs

Capital expenditures are not included in the calculation such as replacing the HVAC system.

Something else to consider is this: the rental income is NOT the only type of revenue properties can produce.

Other sources could include:

  • storage
  • laundry facilities
  • covered parking
  • snow removal
  • vending machines
  • wi-fi

NOI Calculation Example

Dr. A has a son moving off to college and wants to get him started down the “real estate investing” path. He recommended that his son purchase a four-plex to begin to “learn the ropes.”

He was able to locate one within two miles of campus. Currently, each unit rents for $1,200 per month ($4,800 total per month), making the Potential Rental Income $57,600 annually.

There are coin-operated laundry machines in a common area which also bring in $1,000 each year.

He factored in a 10% vacancy loss or $5,760 per year, bringing the Gross Operating Income (GOI) to $51,840. Based on the current owner’s accounting, operating expenses are $12,000 each year.


Net Operating Income = (Gross Operating Income [$51,840]) + (Other Income [$1,000]) – Operating Expenses [$12,000]

Net Operating Income = $40,840 annually

Calculations That Use NOI

Here are 3 real estate calculations that assist investors evaluate potential deals involving NOI:

#1. Cap rate

Net operating income assists investors in determining the cap rate of a property (or capitalization rate). This is a metric used to evaluate the profitability metric of a real estate asset such as a mobile home park.

Typically, investors use cap rates to quickly compare the return on investment (ROI) on different types of property they may be considering buying or selling.

These may vary by:

  • rental rates
  • construction type
  • location

A good rule of thumb to remember is:

  • the lower the cap rate, the higher the value
  • the higher the cap rate, the lower the value

Cap rate formula

Cap rates are calculated by taking the net operating income and dividing it by the market value.

Cap Rate =  Net Operating Income (NOI) / Value

If the NOI isn’t provided, it can be calculated by taking the income received after expenses have been paid before principal and interest payments, capital expenditures, depreciation, and amortization.

Speaking of depreciation, it’s one of the BEST kept tax strategies real estate investors utilize. To learn more, check out this video:


#2. Debt service coverage ratio (DSCR)

For financed properties, the NOI is used in the debt coverage ratio (DCR). Lenders use this metric to assess a borrower’s ability to generate sufficient cash flow to meet their debt payments.

It’s calculated by dividing the borrower’s net operating income (NOI) by their total debt service payments.

A DSCR of 1.0 means that the borrower has just enough cash flow to cover their debt payments, while a DSCR of less than 1.0 indicates that the borrower does not have enough cash flow to cover their debt payments.

#3. Cash On Cash Return (CoC)

The cash on cash return is an annual calculation of an investor’s earnings from a property relative to the initial amount they invested to acquire and operate it. In other words, it represents the return on the capital invested in a rental property.

CoC Return = Net Operating Income (NOI) / Total Amount of Cash Invested

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What’s a favorable net operating income (NOI) in real estate? 

A favorable net operating income (NOI) in real estate is the money you earn after paying all the costs of owning a property except your mortgage. If you make more money than you spend, it’s a good NOI!

How can I determine a property’s net operating income?

First, you need to add up all the money you make from renting it out and then subtract all the costs such as maintenance, taxes, and insurance. The result is your NOI.

Is the mortgage payment incorporated into the NOI calculation?

No, the mortgage payment isn’t part of the NOI calculation as it only represents the money you make and spend on the property, not the loan payments.

What is the method for appraising a property’s value using its NOI?

The first step is to know the NOI and the “cap rate,” which is the rate of return expected for that type of property. Divide the NOI by the cap rate, and you’ll get the property’s value.

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