Cost Segregation Studies: Accelerating Depreciation on Commercial Property

By Yarik Yarosh, CPA ·September 5, 2026 ·5 min read

Written by Yarik Yarosh, CPA (US & Canada) September 5, 2026 · FL CPA license AC61704 · CPA Ontario

A cost segregation study is an engineering-based analysis that reclassifies components of a commercial building from the default 39-year depreciation life (or 27.5-year for residential rental) to shorter lives: 5-year, 7-year, or 15-year property. The reclassified components, which include items like flooring, certain electrical systems, plumbing related to specific equipment, parking lots, landscaping, and decorative finishes, become eligible for bonus depreciation (100% in Year 1 under current law) or accelerated MACRS depreciation. A typical cost segregation study reclassifies 20-40% of a building’s cost, creating a front-loaded depreciation deduction that can save tens or hundreds of thousands of dollars in taxes in the year the building is placed in service or acquired.

✓Key takeaway

Cost segregation study basics:

What it does:

A commercial building is ordinarily depreciated over 39 years (straight-line)
A cost segregation study identifies building components that qualify for shorter depreciation lives:
- 5-year property: carpet, decorative lighting, certain electrical (dedicated to movable equipment), specialty plumbing, decorative millwork, removable partitions
- 7-year property: certain furniture, fixtures, and equipment permanently attached
- 15-year property: land improvements (parking lots, sidewalks, landscaping, fencing, exterior lighting, signage, drainage)
- Qualified improvement property (QIP): interior improvements to non-residential property (15-year, bonus eligible)
These shorter-life components are eligible for bonus depreciation or Section 179

How much gets reclassified:

Typical reclassification: 20-40% of building cost
Office buildings: 15-25%
Retail/restaurant: 25-40%
Manufacturing/warehouse: 25-35%
Hotels/motels: 30-45%
Auto dealerships: 25-40%
Self-storage: 25-40%

Cost of the study:

Small properties ($500K-$2M): $5,000-$10,000
Medium properties ($2M-$10M): $10,000-$25,000
Large properties ($10M+): $15,000-$50,000+
The study cost is deductible as a business expense
ROI is typically 5:1 to 20:1 (tax savings / study cost)

Who should get one:

Any business that owns (not leases) commercial real property worth $500,000+
The study is cost-effective even for properties placed in service in prior years (a “look-back” study, using Form 3115 to catch up on the missed depreciation in one year)
The more the building cost, the higher the ROI

Who performs it:

An engineering firm or CPA firm with cost segregation specialists
The IRS requires a “detailed engineering analysis” (not just a desktop estimate)
The IRS published the Cost Segregation Audit Techniques Guide (2022), which is the standard for what the IRS expects

Limitations and risks:

Depreciation recapture at sale: reclassified personal property is subject to ordinary income recapture under IRC 1245
15-year property recapture: Section 1250 property, capital gain with potential 25% rate on unrecaptured Section 1250 gain
If the property is sold within a few years, the recapture reduces or eliminates the benefit
The study must be “reasonable in detail” to survive IRS examination

How does cost segregation work in practice?

Hypothetical example

Round numbers. A small business owner purchases a $1,200,000 commercial building (land value: $200,000, building value: $1,000,000). The building will house their manufacturing operation. They commission a cost segregation study for $8,000.

Without cost segregation:

Building ($1,000,000): 39-year straight-line
Annual depreciation: $1,000,000 / 39 = $25,641/year
Year 1 deduction: $25,641

With cost segregation (study reclassifies 30%):

Component	Amount	Life	Year 1 Deduction
5-year property (carpet, decorative lighting, dedicated electrical)	$120,000	5-yr	$120,000 (bonus)
7-year property (fixtures, equipment)	$50,000	7-yr	$50,000 (bonus)
15-year property (parking lot, landscaping, fencing, signage)	$130,000	15-yr	$130,000 (bonus)
Remaining building	$700,000	39-yr	$17,949
Total	$1,000,000		$317,949

Year 1 comparison:

	Without	With
Depreciation	$25,641	$317,949
Difference		$292,308
Tax savings at 33%	$8,462	$104,923

Additional Year 1 deduction from cost segregation: $292,308 Additional tax savings: $96,461 Study cost: $8,000 Net benefit: $88,461 ROI: 12:1 (tax savings / study cost)

Over 39 years, the total depreciation is the same ($1,000,000). Cost segregation doesn’t create new deductions. It moves deductions from later years to Year 1. The benefit is the time value of money: a dollar of tax savings today is worth more than a dollar in 20 years.

Look-back study (property placed in service in a prior year): If the owner bought the building 3 years ago and didn’t do a cost segregation study:

File Form 3115 (change of accounting method)
Take all missed accelerated depreciation as a catch-up adjustment in the current year (a IRC 481(a) adjustment)
No need to amend prior returns
The catch-up deduction is taken entirely in the year of the accounting method change

Example:

Building placed in service 3 years ago
39-year depreciation claimed: $25,641 x 3 = $76,923
Cost segregation reclassifies $300,000 to shorter lives
Accelerated depreciation that SHOULD have been claimed: significantly more
481(a) catch-up adjustment: the difference between what was claimed and what should have been claimed, taken in one year
This can create a deduction of $200,000+ in a single year

Depreciation recapture at sale: If the building is sold for $1,200,000 after 5 years:

Without cost seg: depreciation claimed = $25,641 x 5 = $128,205
- Remaining basis: $1,000,000 - $128,205 = $871,795
- Gain: $1,200,000 - $200,000 (land) - $871,795 = $128,205
- All Section 1250 gain: taxed at up to 25%
- Tax: approximately $32,050
With cost seg: depreciation claimed = $317,949 (Year 1) + $17,949 x 4 (Years 2-5) = $389,745
- Remaining basis: $1,000,000 - $389,745 = $610,255
- Gain: $1,200,000 - $200,000 - $610,255 = $389,745
- Section 1245 recapture (personal property): up to ordinary rates
- Section 1250 gain (building): up to 25%
- Tax: approximately $110,000

The recapture at sale is $77,950 higher with cost segregation. But the owner saved $96,461 in Year 1 taxes, which has been earning returns for 5 years. At 8% return: $96,461 x (1.08^5 - 1) = $45,300 in investment returns. Net benefit after recapture: $96,461 + $45,300 - $77,950 = $63,811 ahead even after paying the recapture.

The longer you hold the property, the greater the benefit (more years of time-value compounding, same recapture amount).

Illustrative numbers only, not a real client and not advice for your facts.

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Cite this page

Yarik Yarosh, CPA. "Cost Segregation Studies: Accelerating Depreciation on Commercial Property." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-cost-segregation-study-tax-savings

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.