A real estate purchase can create substantial depreciation deductions, but the default tax treatment often spreads building costs over decades. Cost segregation studies identify components that qualify for shorter recovery periods, potentially moving deductions into earlier years. At SWITCH, we offer a study for each qualifying real estate project, with flat-rate pricing and delivery on the exact date quoted. We evaluate whether accelerated depreciation can actually reduce your current tax liability—not simply generate a large deduction you cannot use.
How cost segregation works
Under Internal Revenue Code Section 168, residential rental buildings generally depreciate over 27.5 years and nonresidential real property over 39 years using the general depreciation system. Land is not depreciable. A building acquisition or construction project, however, may include assets that belong in different tax categories.
A cost segregation study separates those assets from the building structure and assigns supportable costs and recovery periods. Depending on their function and the applicable rules, qualifying components may include:
- Five- or seven-year property: Certain appliances, carpeting, equipment and electrical installations dedicated to qualifying equipment.
- Fifteen-year land improvements: Certain parking areas, fencing, landscaping and exterior improvements.
- Qualified improvement property: Certain improvements to the interior of an existing nonresidential building, subject to specific statutory requirements.
Classification depends on facts, not labels. General building wiring, structural walls and other building systems do not become short-life property merely because a report lists them separately. Qualified improvement property under Section 168(e)(6) excludes enlargements, elevators, escalators and the internal structural framework; an acquired building's existing interior does not automatically qualify.
Where bonus depreciation fits
Section 168(k) can accelerate qualifying short-life property further. Under current federal law, eligible property acquired and placed in service after January 19, 2025, generally qualifies for 100% bonus depreciation. Qualifying used property can be eligible, subject to prior-use, related-party acquisition and other restrictions.
The acquisition date matters, including applicable written binding contract rules. Property acquired before January 20, 2025, may remain subject to the earlier phase-down schedule even if placed in service later. We verify acquisition dates, placed-in-service dates, asset eligibility and elections rather than applying one bonus percentage to an entire project. The building itself and land do not qualify for bonus depreciation.
Who qualifies—and who benefits
Cost segregation can apply to qualifying rental properties, owner-occupied business facilities, new construction and substantial renovations. Purchased properties may qualify even when they are not newly built. Personal-use property does not qualify; mixed-use assets require appropriate allocations.
There is no universal property-value threshold that guarantees a worthwhile study. We compare the depreciable basis, likely asset mix, available deductions, holding period and study fee. Smaller projects or properties scheduled for a near-term sale may offer limited net benefits.
A valid deduction is not always a usable deduction
Rental losses are generally passive under Section 469. A large depreciation deduction therefore may be suspended instead of offsetting wages or operating-business income. Real estate professional status requires more than 750 hours in qualifying real property trades or businesses and more than half of the taxpayer's personal-service time in those activities. Employee hours generally count only when the taxpayer owns more than 5% of the employer.
Real estate professional status alone is insufficient: material participation must also be established for the relevant rental activity, considering any valid grouping election. Short-term rentals have different passive-activity classification rules, but they do not automatically produce nonpassive losses. Basis limits, Section 465 at-risk rules and Section 461(l) excess business loss limits may also restrict deductions.
We distinguish between depreciation generated and taxes actually reduced. Suspended losses can have future value, but they are not current cash savings.
The numbers: an illustrative project
Assume an investor buys and places a rental property in service in 2026 for $2 million. A supportable allocation assigns $400,000 to land and $1.6 million to the depreciable assets. An engineering-based study identifies $320,000 of qualifying short-life property.
| Item | Illustrative amount |
|---|---|
| Total acquisition cost | $2,000,000 |
| Nondepreciable land | $400,000 |
| Depreciable basis | $1,600,000 |
| Short-life property identified | $320,000 |
| Potential bonus deduction on those assets | $320,000 |
If all bonus requirements are satisfied and the deduction is fully usable at a 37% federal marginal rate, that $320,000 deduction represents $118,400 of federal tax reduction before other interactions. This is not the incremental benefit compared with ordinary depreciation: the baseline calculation would already include some depreciation on those costs. The remaining building basis also receives regular depreciation.
We model the incremental benefit after baseline deductions, study fees, state adjustments and expected disposition consequences. California does not conform to federal bonus depreciation, so federal results cannot simply be applied to a California return.
What if you already own the property?
A study may still be useful after a property has been depreciated for several years. When an established depreciation method is changed, Form 3115 and a Section 481(a) adjustment can often recognize previously unclaimed depreciation without amending every prior return.
This is not an automatic filing shortcut. The correct procedure depends on the property's history, whether a method of accounting has been established, disposition timing and current IRS accounting-method-change guidance. A lookback study does not make old property eligible for today's bonus rate; the original acquisition and placed-in-service rules still control.
Common mistakes and IRS scrutiny
The IRS Cost Segregation Audit Technique Guide describes characteristics of credible studies, although it is not binding legal authority. A defensible report connects asset classifications to legal support and reconciles allocated costs to the property's tax basis. Unsupported percentages and generic asset lists create avoidable audit risk.
- Insufficient records: Preserve purchase agreements, closing statements, construction invoices, plans, photographs, depreciation schedules and placed-in-service evidence.
- Incorrect land allocations: Land cannot be shifted into depreciable categories merely to increase deductions.
- Ignoring financing elections: A Section 163(j) real property trade or business election requires alternative depreciation for specified real property, including qualified improvement property. Mandatory ADS property is generally ineligible for bonus depreciation.
- Overlooking recapture: A later sale can trigger ordinary-income recapture under Section 1245 for qualifying assets and other depreciation-related gain treatment under Section 1250.
Cost segregation primarily changes deduction timing. It reduces adjusted basis and can increase taxable gain when property is sold. We consider these trade-offs before recommending acceleration.
How we implement cost segregation at SWITCH
We begin with the project's ownership, basis, use, acquisition history and tax profile. We evaluate deduction limitations and projected holding periods, then scope a study for each qualifying real estate project. Each study is flat-rate priced and delivered on the exact date quoted.
Our implementation process connects the study to depreciation schedules, applicable elections, federal and state reporting, and any required accounting-method change. We also identify records needed to support the classifications. SWITCH is not a law firm and does not provide legal advice; when a broader plan involves complex legal structures, we coordinate execution with licensed attorneys.
Request a free consult with our team to evaluate whether a cost segregation study fits your property, tax position and long-term plans.