A cost segregation study can create meaningful tax benefits, but those benefits are only as strong as the analysis supporting them. If a study is incomplete, poorly documented, or not tailored to the property, owners may miss deductions or face support issues if the results are reviewed. Especially as AI becomes more common in cost segregation workflows, owners should be careful to evaluate a study by more than just the speed, cost, or the size of the projected benefit.

What Is a Cost Segregation Study?

A cost segregation study identifies portions of a property’s cost basis that may be depreciated over shorter recovery periods for federal income tax purposes. Classifying a portion of the property’s basis as shorter-life property can accelerate depreciation deductions and improve after-tax cash flow.

Reclassified items often include portions of electrical or plumbing systems serving specific equipment, specialty lighting, removable finishes, decorative moldings, and site improvements such as parking areas, sidewalks, and landscaping.

While many owners are understandably focused on the final results, the reliability of those results depends on the information considered, the methodology applied, and the support behind the classifications.

What the IRS Considers a Quality Study

A reliable study should reflect the specific facts of the property, available cost records, construction or acquisition history, and applicable tax guidance. The IRS Cost Segregation Audit Technique Guide (ATG) is not binding authority, but it is a useful reference for understanding how examiners will evaluate cost segregation studies.

The ATG does not prescribe one required methodology. It does, however, emphasize that studies based on actual cost records or sound engineering estimating techniques produce more reliable allocations. It also describes a “quality study” as one that is accurate and well documented. A study that reflects the quality principles described in the ATG is better positioned to be supported in any potential audit.

Questions to Ask a Cost Segregation Provider

Owners should consider whether the individual or team they choose to engage has a process that consistently follows those guidelines. A quality provider should be able to explain the analysis process in practical terms and answer a few straightforward questions, regardless of the tools used:

• Who prepared and reviewed the study?
• Does the preparer have both tax knowledge and construction, engineering, and/or cost-estimating experience?
• What property-specific records and physical characteristics were considered?
• How were costs allocated and asset classifications supported?
• Do the reclassified amounts reconcile to the property’s total recorded depreciable basis?
• What study documentation would be available if the study were later reviewed or examined?

These questions are especially relevant as automated technology becomes more integrated into the study process. AI tools can help organize information, identify patterns, and automate repetitive tasks, but the engineering work performed, project information considered, and assumptions relied upon still need to be properly documented. Without that support, an analysis may appear to be a “quality study” while leaving the taxpayer open to unnecessary exposure and audit risk.

Why Professional Judgment Still Matters

Experienced judgment becomes even more valuable as the cost and complexity of a construction project or acquisition increase. Larger projects and acquisitions often involve tenant improvements, specialized equipment, varying types of indirect costs, change orders, and capitalization decisions that may not be clear from the available information. A qualified professional can evaluate whether additional information is needed, whether allocations are reasonable, and advise the taxpayer as to how the study fits into their broader tax and depreciation planning.

How Cost Segregation Supports Long-Term Asset Planning

As property holdings grow, cost segregation often intersects with how fixed assets are treated and depreciated over time. When building components are later replaced, the detailed cost breakdown from a study can support the disposition of assets that are no longer in service. That same component-level detail may also help distinguish a deductible repair from a capital improvement under the tangible property regulations as future work is performed.

For owners with growing portfolios or ongoing construction activity, having an ongoing advisor relationship with a capitalization expert can be especially valuable. A knowledgeable advisor can help develop a more consistent, supportable capitalization approach, keep fixed asset detail more useful over time, and identify issues earlier in the process.

The Appropriate Role of AI in Cost Segregation

Used well, AI should improve efficiency and allow professionals to spend more time on review, higher-level analysis, and advisory work. Used poorly, it can create a false sense of accuracy if the underlying data, methodology, or review process is weak. For owners, the key is to consider whether the product and provider are appropriate for the size, complexity, and risk profile of the property.

Technology may change how cost segregation studies are prepared, but the standard for relying on them should remain the same: the analysis should be documented and tailored to the property.

Tanner Hillman authored this article.