Not long ago, I sat down with the CFO of a 14-property hospitality group operating midscale hotels across the Southeast of the US. They had been using a national accounting firm that outsourced cost segregation to a subcontractor with little understanding of the asset mix common in hospitality.Â
As a result, critical components (like commercial laundry systems, parking areas, and kitchen-specific improvements) were lumped into a 39-year property.
After introducing them to a firm that specialized in hospitality and mixed-use assets, they reanalyzed just three locations and unlocked nearly $900,000 in first-year deductions. That single pivot accelerated their renovation timeline by 12 months.
This kind of result isn’t rare. The right cost segregation company doesn’t just increase your deductions; it reshapes your cash flow and reinvestment strategy. The challenge is knowing who to trust. In 2025, several firms claim engineering precision and audit readiness. Only a few consistently deliver both.
Top 3 Quick Picks: Best Cost Segregation Companies in 2025
1. RE Cost Seg: Best for Full-Service Tax Strategy Integration
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- National expertise, local insight
- Strategic CPA-ready deliverables
- ROI-focused engineering studies
2. CSSI: Best for Fast, Nationwide Coverage
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- 50,000+ studies completed
- Quick, audit-ready documentation
- Full-service across all 50 states
3. Seneca Cost Seg: Best for Boutique, High-Touch Service
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- White-glove project management
- Strong communication and support
- Hands-on with smaller portfolios
For deeper analysis and a breakdown of all eight firms, including specialties and use cases, keep reading.
How to Evaluate a Cost Segregation Company in 2025
A few years ago, a commercial property owner showed me a cost segregation report they had received from a low-cost provider they found online. It was a rushed desktop study, no site visit, no blueprint review, and the depreciation schedules were vague to the point of being unusable. Worse, when the IRS issued a document request, the provider went silent. That mistake forced them to pay for a second study. This time, from a real engineering team, costing twice as much but finally delivering the deductions they were after.
This isn’t uncommon. Choosing the wrong provider can cost you more in missed opportunities, audit exposure, and rework than the initial price tag suggests. But picking the right partner? That can unlock strategic tax savings that compound year after year.
1. Verify Industry-Specific Experience
A firm that excels in industrial properties may not catch the nuances of medical or hospitality assets. Specialized experience leads to sharper classifications and better outcomes. Ask for case studies or references in your sector. It’s one of the fastest ways to separate generalists from experts.
2. Understand Their Engineering Methodology
Engineering-based studies with site visits are still the gold standard. Firms that skip the fieldwork often miss high-value assets or misclassify property. Confirm whether their team includes licensed engineers and how much time is spent onsite versus working from estimates.
3. Check Audit Support and Compliance Standards
Your provider should stand behind its work. Ask about audit history, documentation protocols, and whether they offer representation if the IRS comes calling. Solid firms can walk you through how their studies have held up under scrutiny, and that peace of mind is worth every dollar.
4. Evaluate Reporting Clarity and Deliverables
Great results mean little if the final report confuses your CPA. Look for providers with clean, structured, and CPA-ready documentation. You want breakdowns that flow directly into Form 4562, not summaries that require another round of interpretation.
5. Assess Technology and Turnaround Speed
Some firms offer digital intake portals, AI tagging tools, and cloud-based reporting. These tools streamline delivery without sacrificing accuracy. That said, be wary of firms that promise ultra-fast turnarounds without explaining how they maintain quality and engineering rigor.
6. Confirm Portfolio and Multi-State Capabilities
If your holdings cross state lines, your provider must understand regulatory differences and scale reporting accordingly. National firms with local insight can help ensure consistency while adapting to jurisdiction-specific rules. Critical for REITs, franchises, or institutional portfolios.
The 8 Best Cost Segregation Companies Compared
1. RE Cost Seg: Best for Full-Service Tax Strategy Integration
- Founded: 2022
- Headquarters: Houston, TX
Why RE Cost Seg is the best cost segregation company:Â
RE Cost Seg integrates cost segregation into a broader tax strategy, aligning depreciation studies with long-term financial planning. Their engineering-backed reports are tailored to both property type and ownership structure, which makes implementation seamless for CFOs, CPAs, and family offices alike.
Clients highlight their clarity of reporting, responsiveness, and ability to model ROI on a per-asset basis. Whether managing a single building or a multi-state portfolio, RE Cost Seg’s process delivers both precision and practicality, backed by a team that understands tax code nuance and investment timing.
Their approach isn’t one-size-fits-all. It’s strategic, scalable, and results-driven.
2. CSSI: Best for Fast, Nationwide Coverage
- Founded: 2000
- Headquarters: Baton Rouge, LA
CSSI has completed more than 50,000 studies across all 50 states, offering a rare combination of scale, speed, and IRS compliance. Their no-cost preliminary analysis gives owners a fast sense of potential savings before committing.
Known for rapid turnaround and engineering rigor, CSSI is a favorite for investors working across large portfolios or facing tight filing deadlines. The firm also supports 179D and R&D tax studies, making it a strong one-stop shop.
3. Seneca Cost Seg: Best for Boutique, High-Touch Service
- Founded: 2024
- Headquarters: Albany, OR
Seneca Cost Seg caters to owners who want a more personal, hands-on experience. Their team manages each engagement directly, providing concierge-level service for mid-sized portfolios and specialty assets.
With a focus on communication, responsiveness, and education, Seneca stands out among boutique firms. Their reports are not just audit-ready, they’re client-ready. Designed for owners who want clarity without jargon.
4. KBKG: Best for Complex, Multi-State Portfolios
- Founded: 1999
- Headquarters: Pasadena, CA
KBKG is built for scale and complexity. Their national team spans multiple offices and includes both engineers and tax experts with deep experience in multi-jurisdictional studies.
Known for their proprietary Residential Cost Segregator® and strong audit defense, KBKG is ideal for organizations with holdings across regulatory environments. Their compliance-first approach and engineering methodology make them a trusted name in risk-sensitive projects.
5. McGuire Sponsel: Best for CPA Partnerships
- Founded: 2007
- Headquarters: Indianapolis, IN
McGuire Sponsel was built to complement CPA firms, not compete with them. Trusted by more than 450 accounting firms, their cost segregation work is rooted in engineering precision, with site visits and full blueprint analysis baked into every project.
Deliverables are tailored for integration into CPA workflows, minimizing back-and-forth and maximizing accuracy. For accounting teams looking for a white-label solution with technical depth, McGuire Sponsel is a standout.
6. Engineered Tax Services: Best for Technical Rigor Nationwide
- Founded: 2001
- Headquarters: West Palm Beach, FL
As a licensed engineering firm, ETS brings unmatched technical depth to its cost segregation work. Studies include full blueprint review, asset-level photography, and field-inspected classification. Their Tele‑Engineering™ platform allows remote execution without cutting corners.
ETS completes thousands of studies annually and is often the go-to for complex medical, hospitality, and mixed-use assets requiring precision and regulatory alignment.
7. Duffy + Duffy: Best for Industrial and Manufacturing Assets
- Founded: 2002
- Headquarters: Westlake, OH
Duffy + Duffy focuses on heavy-use commercial and manufacturing properties, where specialized systems like HVAC, utility lines, and equipment pads can shift large portions of cost basis into shorter lives.
Their work is grounded in case law, construction insight, and full engineering fieldwork. LEED projects and environmentally complex sites are a specialty, with documentation tailored for audit defense.
8. Cost Seg EZ: Best for Small Business Owners
- Founded: 2015
- Headquarters: Princeton, NJ
Cost Seg EZ offers streamlined, affordable services geared toward small commercial properties. Think retail, office condos, and restaurants. Their pricing model and simple intake process appeal to business owners managing properties under $2 million.
While they don’t always provide full engineering site visits, they deliver consistent documentation and clear reporting that gets the job done for straightforward assets. A solid pick for budget-conscious owners who still want quality results.
Turning Cost Segregation Into a Strategic Advantage
Cost segregation isn’t just about accelerating depreciation; it’s about unlocking capital you already control. But the impact hinges entirely on execution. The firms in this guide represent the top tier of 2025’s providers, each excelling in a different strategic category: from rapid turnaround to investor-focused service, from industrial specialization to CPA integration.
The best providers don’t just run numbers; they deliver clarity, audit confidence, and alignment with your broader tax and investment strategy. Whether you’re managing a single Class C office building or a diversified national portfolio, the right partner makes the difference between a basic compliance document and a true financial lever.
Choosing wisely is less about cost and more about capability. In today’s environment, that’s not optional. It’s foundational.
Disclaimer: This article contains sponsored marketing content. It is intended for promotional purposes and should not be considered as an endorsement or recommendation by our website. Readers are encouraged to conduct their own research and exercise their own judgment before making any decisions based on the information provided in this article.
