When Should Property Owners Consider a Cost Segregation Study?

Property owners should consider a cost segregation study any time they purchase, construct, renovate, or expand their commercial or residential buildings. A cost segregation study reclassifies certain building components into shorter depreciation categories, allowing owners to accelerate deductions and improve cash flow in the near term rather than waiting decades. With 100% bonus depreciation now permanently restored for qualifying assets placed in service after January 19, 2025, the potential savings are significant. Even owners of older properties can benefit through retroactive “look-back” studies that capture missed depreciation without amending prior returns.

What Is a Cost Segregation Study?

A cost segregation study, also known as a “cost seg”, is an engineering-based analysis that separates a building’s components into different asset classifications based on their useful life. Under standard IRS depreciation rules, commercial real estate is depreciated over 39 years, and residential rental property is depreciated over 27.5 years. But not every part of a building is truly a long-lived asset. Certain elements, including specialized electrical systems, flooring, cabinetry, landscaping, parking lots, and decorative finishes, may qualify for depreciation over 5 or 15 years instead.

The study identifies these shorter-lived components and reclassifies them to accelerate their depreciation. When paired with bonus depreciation, the effect can be substantial. On a $3 million building, for example, a cost segregation study might identify $600,000 or more in assets eligible for immediate or accelerated write-offs. The result is a reduction in current-year tax liability and more available cash for reinvestment, debt reduction, or operations.

A qualified cost segregation study is typically conducted by a team with engineering and tax expertise and follows IRS guidelines to ensure findings hold up under scrutiny. The quality of the study matters, as proper documentation and classification are what separate a defensible analysis from one that creates risk during an audit.

Key Situations When a Cost Segregation Study May Make Sense

Not every property or timing scenario produces the same results. Here are several common situations where the benefits tend to be most pronounced.

After Purchasing a Commercial or Residential Investment Property

Acquiring a property is one of the most natural trigger points for a cost segregation study. Whether you are purchasing an office building, medical facility, retail space, warehouse, or multifamily property, the study can be performed based on the purchase price to identify components that qualify for shorter depreciation schedules. The earlier you conduct the study after acquisition, the sooner you can begin capturing those accelerated deductions.

Following Major Renovations or Tenant Improvements

Significant buildouts and interior renovations often involve assets that qualify for shorter recovery periods. Lighting upgrades, HVAC installations, specialized wiring, and tenant-specific finishes are among the items that can be reclassified. Interior improvements to nonresidential buildings may also qualify as Qualified Improvement Property (QIP), which carries a 15-year depreciation life and is fully eligible for bonus depreciation. If you have recently invested in substantial tenant improvements, a cost segregation study can help ensure you’re capturing the full tax benefit of those expenditures.

During or After New Construction Projects

New construction offers the clearest opportunity for a cost segregation study because detailed cost records are typically available from the beginning. Blueprints, contractor invoices, and construction budgets provide the documentation needed to identify and categorize qualifying assets with precision. Conducting the study during or immediately after construction allows owners to start recognizing accelerated deductions in the very first year the building is placed in service.

When Expanding or Remodeling an Existing Facility

Facility expansions and remodels introduce new building components that qualify for accelerated treatment. Additions, structural modifications, and upgraded systems all present opportunities for reclassification. In many cases, the cost segregation study can also support partial asset dispositions. When older building components are replaced during a remodel, the remaining undepreciated value of those retired assets may be written off, providing an additional deduction that property owners frequently overlook.

Can You Perform a Cost Segregation Study on an Older Property?

Yes. A common misconception is that cost segregation studies are only useful at the time of purchase or construction. In reality, owners of properties placed in service years ago can still benefit through what’s known as a “look-back” or retroactive study. The IRS allows taxpayers to claim previously missed accelerated depreciation through a change in accounting method using Form 3115. The catch-up deduction is taken in a single tax year, with no need to amend prior returns.

For owners who have been depreciating their property over 39 or 27.5 years without ever performing a cost segregation study, the cumulative missed depreciation can be substantial. A look-back study identifies those overlooked deductions and brings them forward, creating an immediate tax benefit. Whether your building was purchased five years ago or fifteen, a retroactive study is worth evaluating.

Evaluate Cost Segregation Opportunities With Insero

Every property tells a different story when it comes to depreciation, and the right analysis can uncover savings that have been sitting untapped for years. Insero’s cost segregation consultants work with property owners to conduct detailed, engineering-based studies that identify assets eligible for accelerated depreciation. We analyze your property’s components, from electrical and plumbing systems to site improvements and interior finishes, and reclassify them into the appropriate recovery periods to maximize your tax position.

Our team brings deep experience across property types and industries, and we coordinate closely with your existing tax advisors to ensure a seamless process. Whether you have recently acquired a property, completed a renovation, or simply want to explore whether a look-back study makes sense for a building you have owned for years, we can help you quantify the opportunity and build a strategy around it.

Contact Insero today to schedule a consultation and find out how a cost segregation study could improve your cash flow and reduce your current tax liability.

Resources:

• https://www.irs.gov/publications/p946
• www.irs.gov/taxtopics/tc704
• https://www.irs.gov/forms-pubs/about-form-3115