Same-Store NOI: The Organic REIT Performance Measure

Key Takeaways

• Same-store NOI growth strips out acquisitions and dispositions to show organic portfolio performance; apartment REITs saw double-digit same-store NOI growth in 2021 to 2022 while office REITs posted negative growth simultaneously.
• Typical same-store NOI growth runs 2 to 4 percent in normal conditions; sustained growth above that range signals genuine rent market strength, while growth below 0 flags structural demand problems.
• A common mistake is comparing same-store definitions across REITs, since each company defines the eligible pool differently, some exclude redevelopment, some use 12-month seasoning, others use 13 months.
• Expense inflation can eat rent growth entirely; property tax and insurance cost increases after 2022 turned 5 percent rent growth into weaker same-store NOI at many REITs.

What It Is

Net operating income (NOI) is rental revenue plus ancillary property income (parking, fees) minus direct operating expenses (property management, maintenance, utilities, insurance, property taxes). It excludes mortgage interest, corporate overhead, depreciation, and income tax.

Same-store NOI applies that calculation only to properties a REIT has owned for both the current period and the year-ago comparison period, typically at least one full fiscal year. The year-over-year change in same-store NOI is called same-store NOI growth or SS NOI growth.

By stripping out buildings that were bought or sold during the period, same-store NOI growth captures the organic performance of the existing portfolio. That is why analysts and Nareit track it as the primary measure of operating health.

The Intuition

Total NOI can grow for two reasons: the REIT bought more buildings, or the buildings it already owned earned more money. Both matter, but they are very different stories.

A REIT that grows total NOI by 15 percent on the back of a 15 percent acquisition binge is not necessarily getting better. It is just getting bigger, often at the cost of higher leverage and diluted per-share metrics. A REIT that grows same-store NOI by 4 percent has shown that existing tenants are paying higher rent, vacancies are falling, or expenses are under control. That is genuine improvement.

Investors pay more per dollar of NOI when they see consistent organic growth, because organic growth compounds without needing fresh capital.

How It Works

The basic calculation is straightforward.

Same-Store NOI = Rental revenue (same-store properties)
               + Other property income
               - Direct operating expenses

Growth is the year-over-year percent change in that figure.

SS NOI Growth = (SS NOI this period / SS NOI year-ago period) - 1

The judgment calls are in what counts as "same-store." Most REITs require a property to have been owned and stabilized for at least one full year in both the current and prior period. Some exclude properties that are undergoing major redevelopment, because the renovation depresses current-period revenue and inflates the comparison.

The drivers of same-store NOI growth fall into three buckets:

• Rent growth, from contractual escalators on existing leases, mark-to-market on rolling leases, and new leases signed at higher rates.
• Occupancy change, where a one percentage point gain on a 95 percent occupied building is a small number but consistent occupancy gains across hundreds of buildings add up.
• Expense control, including property taxes, utilities, insurance, and repair costs. In inflationary periods, expense growth can eat rent growth.

Typical same-store NOI growth runs 2 to 4 percent for mature, stabilized property types in normal economic conditions. Apartments during the 2021 to 2022 rent spike saw double-digit same-store NOI growth at several large REITs. Office REITs in 2020 through 2022 posted negative same-store NOI as occupancy fell and concessions rose.

Worked Example

An apartment REIT owns 100 properties at the start of Year 1. During the year, it buys 10 new properties and sells 5. At the end of Year 2, the REIT has 105 buildings.

For same-store analysis, the REIT counts only the properties owned through both full periods. That is the original 100, minus the 5 sold, equals 95 buildings.

In Year 1, those 95 same-store properties generated 950 million dollars of NOI. In Year 2, the same 95 properties generated 988 million.

SS NOI Growth = (988 / 950) - 1 = 0.04 = 4.0%

Headline total NOI might have grown 12 percent after adding the 10 new properties, but the same-store number tells you the existing portfolio grew 4 percent. That is the number to compare against peers, inflation, and the REIT's own history.

Common Mistakes

1. Comparing same-store definitions across REITs. Each REIT defines its same-store pool differently. Some include redevelopment, some exclude it. Some use a 12-month seasoning period, others use 13 months. Read the footnotes before comparing two competitors head to head.

2. Ignoring occupancy when reading rent growth. A REIT can post strong rent growth by dropping occupancy, because only the best tenants renew at top rates. Always check rent growth and occupancy together.

3. Treating one quarter as a trend. Same-store NOI growth swings with seasonality, one-off tax adjustments, and lease roll timing. Look at trailing twelve months or multi-year averages.

4. Forgetting expense pressure. Property taxes and insurance costs jumped sharply in many markets after 2022. Rent growth of 5 percent with expense growth of 8 percent produces weak same-store NOI growth even when the top line looks healthy.

5. Confusing same-store with cash NOI. Cash NOI excludes straight-line rent adjustments and follows actual collections. Reported NOI can be higher than cash NOI when lease escalators are being recognized in advance. Both numbers are useful, but they are not the same.

Frequently Asked Questions

Q: What is same-store NOI in simple terms? Same-store NOI is the net operating income from properties a REIT has owned through both the current period and the year-ago comparison period, expressed as a year-over-year percentage change. It strips out acquisitions and sales so you can see whether the existing portfolio is actually getting better or worse.

Q: How does same-store NOI affect investment decisions? Consistent same-store NOI growth compounds without requiring fresh equity capital. A REIT growing same-store NOI at 4 percent organically is more valuable per dollar of NOI than one achieving the same total NOI growth through acquisitions, because organic growth has no dilution cost. Investors pay higher multiples for REITs with durable same-store growth.

Q: What is a real-world example of same-store NOI? In the worked example, 95 same-store properties grew NOI from $950 million to $988 million, a 4.0 percent gain. Total NOI may have grown 12 percent after adding 10 new buildings, but the same-store number reveals the genuine organic improvement rate that can be compared against peers and the REIT's own history.

Q: How can investors use same-store NOI analysis? Track same-store NOI growth across four to eight quarters to see the trend and account for seasonality. Decompose the growth into rent growth, occupancy change, and expense movement to understand which driver is working. Always check whether the definition is consistent year to year, as changes in the pool definition can distort comparison.

Q: How is same-store NOI different from total NOI? Total NOI includes all properties in both periods, including recent acquisitions. Same-store NOI uses only the subset owned through both periods. A REIT that grew total NOI 15 percent but same-store NOI only 2 percent has grown primarily by buying assets, which may or may not be value-accretive depending on the cap rates paid.

Sources

1. Nareit. "Expansion and Growth of REIT Earnings." https://www.reit.com/news/blog/market-commentary/expansion-and-growth-of-reit-earnings
2. American Association of Individual Investors. "Conducting Fundamental Analysis of Equity REITs." https://www.aaii.com/journal/article/conducting-fundamental-analysis-of-equity-reits
3. AEI Consultants. "How to Calculate NOI in Commercial Real Estate." https://aeiconsultants.com/how-to-calculate-net-operating-income/

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.