Decoupled from OBBBA §168(k)
Delaware Follows Pre-OBBBA Phase-Down (20% Bonus for 2026)
6.6% Top Individual · 8.7% Corporate
Federal Benefit Is Primary
22–35% Typical Reclassification
Delaware Building Value into Short-Life Assets
All Commercial Asset Classes
Statewide Delaware
The Basics
What Cost Segregation Does for Delaware Property Owners
A cost segregation study identifies building components, HVAC systems, specialty flooring, parking surfaces, interior finishes, exterior lighting, that qualify for accelerated depreciation on 5-, 7-, or 15-year schedules rather than the default 27.5-year (residential rental) or 39-year (commercial) building schedule. Front-loading those deductions increases first-year cash flow and lowers current-year federal taxable income.
In Delaware, the federal benefit works the same way it does anywhere, the One Big Beautiful Bill (OBBBA, P.L. 119-21) permanently restored 100% bonus depreciation for qualified property placed in service after January 19, 2025, and that federal benefit applies to Delaware properties in full. State-level treatment is where Delaware changed course in late 2025: HB 255 (signed by Gov. Meyer November 19, 2025) decouples Delaware from OBBBA’s §168(k) and §168(n) provisions for both individuals and corporations. Delaware instead applies §168(k) as in effect immediately before OBBBA, meaning the TCJA phase-down: 40% bonus for 2025, 20% for 2026, 0% for 2027 and later (through the 2030 sunset). Federal bonus depreciation must be added back on the Delaware return, and depreciation is recomputed under the pre-OBBBA phase-down schedule. Your CPA files Form CIT-DCP (HB 255 Decoupling Modification Schedule) for corporate returns.
Federal Benefit Is the Primary Lever
Delaware’s Tax Landscape: Why Cost Segregation Matters Here
Individual Income Tax
Graduated, top rate 6.6% (Del. Code Ann. tit. 30, §1102).
Corporate Income Tax
8.7% flat (Del. Code Ann. tit. 30, 1902), one of the higher corporate rates in the country.
Bonus Depreciation Conformity
Decoupled from OBBBA changes. Delaware HB 255 (signed Nov 19, 2025; DE Division of Revenue TIM 2025-2 dated Dec 23, 2025) applies §168(k) as in effect immediately before OBBBA. Bonus depreciation on the Delaware return follows the TCJA phase-down: 40% for 2025, 20% for 2026, 0% from 2027 through the 2030 sunset. Federal 100% bonus depreciation is added back on the Delaware return.
179 Expensing
Delaware also decouples from OBBBA’s §179 increases under HB 255. Delaware §179 stays at the pre-OBBBA cap (approximately $1.25M for 2025, indexed) rather than the federal 2026 $2.56M cap.
Qualified Production Property (§168(n))
Delaware decouples entirely, no 100% special depreciation allowance on the Delaware return.
No State Sales Tax
Delaware is one of five states with no state sales tax. Not directly relevant to cost segregation but part of the state’s overall tax profile.
Property Tax
~0.61% effective, Delaware runs one of the lower property tax rates in the country. A separate lever from income tax; cost segregation operates on income tax through accelerated depreciation.
§481(a) Catch-Up
For Delaware properties owned more than a year without a study, an automatic accounting-method change (Form 3115 under Rev. Proc. 2015-13 and its updates) captures all missed depreciation into the current tax year at the federal level, no amended returns required.
Every Commercial Asset Class in Delaware
Delaware Property Types Where Cost Segregation Delivers
Banking & financial services
Wilmington’s banking corridor (credit card processing hub, private banking, corporate services) runs high-density office property with specialized systems.
Pharmaceutical & biotech
DuPont legacy operations, Chemours, Incyte, AstraZeneca, and related pharma/chemical facilities across northern Delaware run specialized industrial and research property with strong reclassification content.
Agriculture & food processing
Southern Delaware’s poultry industry (Perdue, Mountaire, Allen Harim) runs processing plants and specialized agricultural facilities with heavy equipment content.
Hospitality & tourism
Rehoboth Beach, Bethany Beach, and Delaware coastal resort corridor hotel and resort property with substantial FF&E.
Healthcare & medical office
ChristianaCare, Nemours, Beebe Healthcare medical office and specialty facility corridors.
Multifamily
Wilmington, Newark, and Middletown/Bear multifamily development.
Retail & mixed-use
Concord Pike, Christiana, and beach-town retail centers.
Corporate office
Delaware’s role as a corporate registration state means significant Wilmington-metro corporate services office property.
Investment residential
5+ unit properties eligible for cost segregation.
Not sure whether your Delaware property qualifies? Request a free benefit analysis, we’ll tell you honestly.
Credentialed. Independent. Nationwide
Why The Ambrose Group?
MAI-certified appraisers, in-house engineer
The IRS prefers engineering-based studies over rule-of-thumb estimates. Our in-house engineer conducts the analysis, reviews construction documents, and physically identifies reclassifiable components. Many providers estimate; we don’t.
IRS-compliant methodology
Every Ambrose study follows the IRS Cost Segregation Audit Techniques Guide (ATG, Publication 5653).
30+ years of nationwide experience
Headquartered in Texas, serving Delaware and all 50 states.
Audit Defensibility
Our engineering-based cost segregation studies are built to hold up, with site inspections, detailed documentation, and support if the IRS ever asks.
CPA-ready reports
We deliver a complete reclassification package your CPA can apply directly, including the depreciation detail your CPA needs to file Form CIT-DCP for Delaware’s HB 255 decoupling.
Single-property to multi-state portfolios
Whether you own one Delaware commercial building or a portfolio spanning multiple states, we scale the engagement to fit.

Real Numbers
What First-Year Savings Might Look Like in Delaware
Results depend on property type, cost basis, construction year, and applicable depreciation rates, and we run a free benefit analysis before you commit to a study so you can see projected numbers first.
As a reference point, an Ambrose Group engagement on a $2.9M commercial property delivered $657,692 in first-year depreciation increase and $230,192 in first-year tax savings. In Delaware specifically, the federal Year 1 savings apply fully; the Delaware state benefit for 2026 follows the pre-OBBBA phase-down (20% bonus for 2026, 0% from 2027), so the state-side benefit is smaller than in full-conformity states. The federal deduction combined with Delaware’s 6.6% top individual rate and 8.7% corporate rate still delivers strong overall value.
Get Started
Free Delaware Cost Segregation Benefit Analysis
Tell us about your Delaware property, asset type, acquisition or construction cost, when it was placed in service, and we’ll run a free benefit analysis showing projected first-year depreciation and tax savings before you commit to a study.
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Right approach for your property type
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Federal benefit modeled + Delaware HB 255 state-timing considerations
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Clear read on the study’s projected ROI
Prefer to talk? Call us directly:
(713) 688-7733
The Ambrose Group headquarters, Jersey Village, TX (serving Delaware and all 50 states).
Request Your Free Analysis
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How It Works, Delaware & Nationwide
Our Cost Segregation Process
What Clients Say
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Cost Segregation in Delaware
Frequently Asked Questions
Does Delaware conform to federal bonus depreciation rules?
No, not for property placed in service after January 19, 2025. Delaware HB 255 (signed November 19, 2025) decoupled Delaware from OBBBA’s §168(k) 100% bonus depreciation and §168(n) qualified production property provisions for both individuals and corporations. Delaware applies §168(k) as in effect immediately before OBBBA, so the TCJA phase-down applies on the Delaware return: 40% bonus for 2025, 20% for 2026, 0% for 2027 through the 2030 sunset. Your federal Year 1 tax savings from a cost segregation study are fully preserved; the Delaware benefit is smaller and diminishing through the decoupling sunset.
How does Delaware’s state income tax interact with a cost segregation study?
Delaware has a graduated individual income tax topping at 6.6% and a flat 8.7% corporate income tax. Because Delaware decoupled from OBBBA’s bonus depreciation restoration under HB 255, the state-level Year 1 benefit follows the pre-OBBBA phase-down, 20% for 2026. The federal deduction still applies at the federal marginal rate, and combined with Delaware’s rate structure, the federal side is where the study’s economics primarily live.
What Delaware commercial property types benefit most from cost segregation?
Wilmington banking and financial services office, DuPont/Chemours/Incyte/AstraZeneca pharmaceutical and biotech facilities, southern Delaware poultry processing (Perdue, Mountaire), beach-corridor hospitality, medical office along the ChristianaCare and Nemours corridors, and Wilmington-metro multifamily. Specialized industrial and pharma facilities produce the strongest reclassification outcomes.
Can I do a cost segregation study on a Delaware property I’ve owned for years?
Yes. A 481(a) adjustment via an automatic accounting-method change (Form 3115 under Rev. Proc. 2015-13 and its updates) lets you capture all missed depreciation from prior years into the current tax year without amending past returns. Especially valuable for long-held Delaware commercial and industrial properties.
How do you do a cost segregation study on a Delaware property when you’re based in Texas?
Cost segregation is governed by federal tax law, so the methodology is identical regardless of state. Our engineer works either through an in-person Delaware site visit or, for well-documented properties, a virtual site inspection using high-definition video, construction documents, and interactive tools. Both are IRS-compliant. Delaware’s small footprint makes on-site visits efficient.
What construction era of Delaware property produces the strongest cost segregation outcomes?
Properties placed in service since 1987 are eligible under current IRS guidance, and studies limited to the last 7–10 years tend to deliver the strongest ROI. Delaware’s biotech, banking corridor, and beach-town multifamily development pipelines have produced substantial newer property in the ideal window.
Does Delaware’s low property tax rate affect the cost seg decision?
Cost segregation reduces income tax through accelerated depreciation, not property tax. Delaware’s effective property tax rate (~0.61%) is moderate, but that’s a separate lever from the income-tax benefit cost segregation delivers.
What documentation do you need for a Delaware cost segregation study?
Purchase or construction cost documentation, a current depreciation schedule from your CPA, construction plans or specs (when available), any prior appraisals, and, for renovation studies, improvement records. Because Delaware decoupled from OBBBA bonus depreciation under HB 255, your CPA will need the detailed asset schedule to file Form CIT-DCP (HB 255 Decoupling Modification Schedule). We provide it as part of the standard deliverable.
Can you handle Delaware multi-property portfolios?
Yes. We regularly run cost segregation studies across multi-state and Delaware-only portfolios. Common for pharma operators with multiple Delaware facilities, banking-corridor office portfolios, and poultry-industry facility owners with multiple plants across the state.
How long does a cost segregation study take on a Delaware property?
From engagement to CPA-ready report, most studies run 4–8 weeks depending on property complexity, document availability, and site-visit scheduling. Complex pharmaceutical, biotech, or poultry-processing facilities can take longer proportional to the equipment-cataloging effort.
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Talk to Trusted Cost Segregation Consultants
We live by our motto: “Everything we do is driven by the relationship, not the transaction”, and we mean it. Whether you have a Delaware property to evaluate or a multi-state portfolio to review, we’re here to help. Contact our real estate firm.
