5 Cost Segregation Providers CPAs and Owners Can Evaluate in 2027

A cost segregation study reclassifies parts of a building, like carpeting, wiring, or parking lots, into shorter depreciation categories so an owner can write off more of the property faster. That one decision can move real cash into an investor's pocket years before a standard 27.5- or 39-year schedule would get around to it. The hard part isn't understanding the concept. It's figuring out which firm will actually deliver a study that holds up and pays for itself.

The five firms below all work in this space, though not all of them run the same way. Some bolt cost segregation onto a broader menu of tax credits. Others treat it as the one thing they do all day. Knowing the difference matters more than it sounds like it should.

Best for Specialist Focus and Faster Turnaround – R.E. Cost Seg

R.E. Cost Seg helps investment real estate owners accelerate depreciation, lower current taxable income, and free up cash for reinvestment through cost segregation studies. The firm's positioning is built entirely around this one service rather than a broader tax practice, and that shows up in how it's structured day to day.

Because cost segregation is the only thing on the firm's plate, a study can go deeper on a given property and move through review faster than it typically would inside a general accounting practice that's also handling payroll, audits and a dozen other client needs. For owners, that translates into larger deductions landing sooner and more usable cash in the years right after a purchase or renovation.

CPAs and financial advisors who don't want to build their own cost segregation function can also bring the firm on as a white-glove partner, handing off the technical study and the client-facing explanation while keeping the relationship under their own name. That setup suits a CPA who wants the benefit on a client's return without adding a new specialty to their own practice.

Anyone comparing firms on this list for recent client feedback can start with the R.E. Cost Seg reviews page before deciding who to call first.

Best for Firm-Wide Tax Benefit Scale – KBKG

KBKG runs a national practice covering cost segregation, R&D tax credits, 179D deductions, transfer pricing and transferable credits, alongside software built for CPAs and smaller firms that want to run parts of the process themselves. The firm reports over $11 billion in Tax Benefits Claimed across its client work, a figure that reflects a practice built on volume across several credit types rather than one niche.

Its team includes former Big-4 leaders and has operated for a proven track record over 25 years, which has earned it trust from thousands of CPAs who refer client work its way. The trade-off is that cost segregation sits alongside several other service lines here rather than being the singular focus, so clients are tapping into one piece of a much larger practice rather than a team that does nothing else.

Best for Multi-Service Steuerberatung – Leyton

Leyton is an international consulting firm built around Innovationsförderung, steuerliche Forschungsförderung and performance optimization work for businesses. Its German-facing site centers on Fördermittel für Unternehmen, covering national funding programs, EU funding, VAT compliance and the Forschungszulage research tax credit.

This is a generalist tax and funding consultancy rather than a cost-segregation specialist, which fits a business that wants one advisor handling several categories of government incentives at once. The flip side is that a property owner looking specifically for a deep-dive depreciation study is one of several things this firm does, not the single discipline it has built its name on.

Best for High-Volume Engineering-Based Studies – Engineered Tax Services

Engineered Tax Services is an independent, professionally licensed engineering firm that performs over 10,000 cost segregation, 179D and R&D tax studies a year for clients across the United States. That volume points to a firm built for throughput, with engineers rather than general accountants doing the underlying technical work.

The firm is rated 4.8/5 on Google Reviews and prices each study with a custom quote based on project scope, so cost depends on the specific property rather than a flat fee. Running studies at that scale across three different credit types means the firm's attention is split across a wide service menu, which may matter to an owner who wants a team focused on cost segregation alone.

Best for Property Owner Fundamentals – CSSI

CSSI covers cost segregation for property owners, R&D tax credits for businesses and 179D deductions for energy-efficient buildings under one roof. That combination makes it a reasonable stop for an owner who might also want to explore energy-efficiency deductions down the line without switching firms.

What a Cost Segregation Study Actually Involves

A typical study starts with a site visit or a detailed review of construction documents, invoices and blueprints. An engineer or cost segregation specialist then separates the building's components into IRS-recognized categories, usually 5-, 7-, or 15-year property, instead of leaving everything on the standard 27.5-year (residential) or 39-year (commercial) schedule.

The payoff comes from timing, not from creating new deductions out of nothing. Moving a portion of a building's value into a 5-year bucket means that value gets written off far sooner, which lowers taxable income in the years right after a purchase, renovation, or new construction. That freed-up cash is often reinvested into another property or used to cover near-term expenses.

Not every property benefits equally. A study tends to pay for itself fastest on properties with a high purchase price, a recent acquisition date, or significant renovation work, since there's more value to reclassify and more years left on the depreciation clock to accelerate. An older property close to the end of its depreciation schedule has less room to gain.

Anyone running the numbers on a fulfillment center or warehouse acquisition might also find it useful to look at how operators pick the right fulfilment and warehouse management systems, since the same cost-benefit thinking applies when weighing a new system investment against its payback period.

For background on how the IRS treats depreciation recapture and asset classification, the IRS's Cost Segregation Audit Techniques Guide lays out how examiners actually review these studies, which is worth a skim before signing off on any firm's numbers.

Matching the Firm to What Your Property Actually Needs

A CPA weighing whether to build an in-house cost segregation function or hand it off should think about volume first. One or two client studies a year rarely justifies the overhead of training staff and buying software, which is where a dedicated partner firm earns its keep. A firm processing that work constantly for dozens of clients might look harder at a platform-based option that keeps more of the process in-house.

Property type matters too. A single commercial building with a straightforward purchase history is a different job than a portfolio spanning multiple asset classes and renovation timelines. The latter benefits from a firm that can move fast across several properties without losing accuracy on any one of them.

For an investor who wants a team whose entire practice is built around getting a depreciation study right and done quickly, R.E. Cost Seg's single-service structure is the clearest fit on this list. CPAs who'd rather not build a cost segregation desk of their own get the same benefit by handing the technical work to a partner who treats it as their core job rather than one line on a longer service menu.