A few years ago, I met a private investor who owned several multifamily properties and was preparing to roll gains from one project into new construction. During our discussion, he mentioned that he’d never commissioned cost segregation studies on any of his existing assets. The oversight meant he had never accelerated the allowable depreciation during ownership. Missing years of potential tax savings and liquidity that could have strengthened his next investment cycle.
What struck me wasn’t the mistake itself, but the lost opportunity. With the right cost segregation partner early in the ownership timeline, that investor could have improved his internal rate of return, increased after-tax cash flow, and reinvested far more aggressively.
That’s the real power of strategic cost segregation. It’s not just about compliance. It’s about timing, insight, and execution. The firms in this list represent the best cost segregation companies in 2025, each combining engineering precision with financial foresight to help property owners unlock capital when it matters most.
Quick Take: The Best Cost Segregation Companies for 2025
1. RE Cost Seg: Best for Proactive Tax Strategy
- Engineering-led planning process
- Integrated tax and cash flow modeling
- Tailored studies for growth-focused investors
2. Haynie & Company: Best for Full-Service CPA Integration
- National CPA firm with an in-house cost segregation team
- Ideal for complex accounting environments
- Strong audit defense and documentation standards
3. Cost Seg EZ: Best for Mid-Sized Portfolios
- Fast digital intake and reporting
- Lower-cost studies for smaller assets
- CPA-reviewed results for reliability
These three firms reflect the evolving landscape of cost segregation in 2025, from integrated tax strategy to technology-enabled efficiency. Keep reading for the full list of six top-performing companies and insights on how to match each one to your portfolio’s needs.
Choosing the Best Cost Segregation Provider for Your Property
1. Early-Stage Engagement
Engaging a provider early (ideally before or during acquisition) allows them to review construction budgets, design details, and cost breakdowns while the data is still accessible. Early coordination leads to cleaner classifications and stronger audit support, and it ensures the study is positioned as part of your tax strategy rather than a year-end scramble.
2. Engineering and Construction Expertise
The quality of a cost segregation study depends heavily on technical depth. Firms with licensed engineers and construction specialists bring an understanding of materials, systems, and site improvements that paper-based methods can’t replicate. Their ability to trace costs to specific building components directly impacts the accuracy of your deductions.
3. Tax Integration and CPA Collaboration
Strong firms don’t work in isolation. They partner with your CPA or in-house tax department to ensure the findings flow seamlessly into your returns. A coordinated provider can anticipate how reclassification will affect your broader depreciation schedule, reducing the risk of filing discrepancies or missed opportunities.
4. Audit Defense and Documentation Quality
Reputable providers build every study as though it will face IRS review. Look for comprehensive workpapers, photographic documentation, and clear explanations of classification logic. Firms that include audit defense within their standard engagement signal confidence in their methodology and commitment to compliance.
5. Multi-State and Multi-Property Experience
If you operate across multiple states, your provider should be fluent in regional variations and local compliance nuances. Multi-property experience also indicates the firm’s ability to manage consistent methodology across a portfolio, an essential factor for investors and REITs.
6. Transparency in Pricing and Deliverables
The best cost segregation companies are upfront about what you’re paying for (engineering labor, site visits, revisions, and audit support). Flat-fee pricing models often reflect process maturity and reduce uncertainty for clients managing multiple properties or tight timelines.
7. Long-Term Partnership and Portfolio Strategy
A strong cost segregation relationship doesn’t end with a report. The right provider continues to add value over time, advising on partial dispositions, renovations, and portfolio updates. Firms that proactively revisit completed studies or adapt to tax law changes help clients maintain compliance and sustain long-term savings.
The 7 Top-Rated Cost Segregation Companies for 2025
1. RE Cost Seg: Best for Proactive Tax Strategy
- Founded: 2022
- Headquarters: Houston, Texas
Why RE Cost Seg is the best cost segregation company:RE Cost Seg approaches every engagement as a long-term financial partnership rather than a transactional study. Their engineering-based process is paired with sophisticated tax planning, helping property owners identify, quantify, and strategically time their depreciation deductions.
The firm’s reports go beyond compliance, providing cash flow projections and ROI modeling that allow investors to visualize the real impact of accelerated depreciation. With a national reach and a reputation for precision, RE Cost Seg continues to set the benchmark for results-driven, audit-ready cost segregation in 2025.
2. Haynie & Company: Best for Full-Service CPA Integration
- Founded: 1960
- Headquarters: Salt Lake City, Utah
Haynie & Company stands out for combining a national accounting presence with in-house cost segregation expertise. This integration allows for complete oversight of tax strategy, financial reporting, and audit defense under one roof.
Their multidisciplinary team of CPAs and engineers works seamlessly across sectors, particularly with developers and business owners who value consistent communication and data integrity throughout the depreciation process.
3. Cost Seg EZ: Best for Mid-Sized Portfolios
- Founded: 2015
- Headquarters: Princeton, NJ
Cost Seg EZ has built a reputation for delivering fast, affordable, and audit-ready cost segregation studies designed for small- to mid-sized property portfolios. Their digital-first process streamlines data collection and reporting, allowing clients to receive fully CPA-reviewed studies without the delays typical of larger firms.
The firm’s model focuses on balancing efficiency with accuracy. Clients benefit from clear, engineering-based documentation that integrates seamlessly into existing tax workflows. Cost Seg EZ’s approach makes it an ideal choice for investors and owner-operators who want reliable, IRS-compliant results without paying enterprise-level fees or sacrificing turnaround speed.
4. Engineered Tax Services: Best for Technical and Structural Expertise
- Founded: 2001
- Headquarters: West Palm Beach, Florida
Engineered Tax Services (ETS) brings licensed engineering authority to the tax space, performing studies grounded in structural evaluation and detailed blueprint analysis. Their combination of technical rigor and tax fluency ensures compliance even for the most complex projects.
ETS also pioneered remote verification technology through its Tele-Engineering™ program, allowing for precision without the logistical cost of frequent travel. Ideal for national portfolios with dispersed assets.
5. Maven Cost Seg: Best for High-Complexity and Redevelopment Projects
- Founded: 2023
- Headquarters: Sterling Heights, MI
Maven Cost Seg operates as a boutique consultancy serving developers and investors with architecturally complex or adaptive reuse properties. Their engineers and construction analysts conduct deep, field-based studies that include 3D modeling and cost tracing to validate every classification.
Their hands-on communication style and transparent reporting process make them a preferred choice for developers working on repositioning or renovation-heavy projects.
6. CSSI (Cost Segregation Services, Inc.): Best for Nationwide Coverage and Speed
- Founded: 2000
- Headquarters: Baton Rouge, Louisiana
CSSI continues to be one of the most recognized names in the field, known for completing tens of thousands of studies across all 50 states. Their methodology emphasizes engineering validation, audit-ready documentation, and rapid delivery without compromising compliance.
Their scale allows them to manage simultaneous studies for multi-state owners, REITs, and franchise operators. Making CSSI ideal for organizations, balancing volume with precision.
7. ELB Cost Seg: Best for Owner-Operators and Small Businesses
- Founded: 2001
- Headquarters: New Port Richey, Florida
ELB Cost Seg caters to owner-operators and smaller commercial property owners who need expert-level quality in a manageable, cost-efficient package. Their engineering-based approach ensures accuracy, while their process is streamlined for clients with limited internal resources.
ELB’s responsiveness, clear deliverables, and competitive pricing have made it a trusted option for small businesses and investors looking to capture value from properties under $10 million.
Turning Depreciation Into Capital: The Strategic Power of Cost Segregation
In the right hands, cost segregation becomes more than a compliance tool. It’s a capital optimization strategy. The strongest firms in 2025 aren’t just calculating depreciation schedules. They’re showing property owners how to convert those numbers into liquidity, reinvestment, and long-term growth.
Each of the seven firms featured here takes a distinct approach. RE Cost Seg leads with forward-thinking tax strategy and measurable ROI analysis. Haynie & Company brings the credibility of a national accounting platform. Boutique providers like Maven Cost Seg and Cost Seg EZ deliver hands-on precision for specialized portfolios. And long-established names such as CSSI, ETS, and ELB continue to set benchmarks for audit readiness and reliability.
The lesson for investors and owners is simple: the right partner changes everything. When engineering insight meets tax planning discipline, depreciation turns from a line item into a growth engine. Helping businesses reinvest faster, operate leaner, and outperform the market.