Cost Segregation: When It's Worth the Fee and When It Isn't

Quick Insights

• If you've bought a rental or commercial property, a cost segregation study can move years of depreciation into your first year of ownership. Your total deductions over the life of the property stay the same.
• Whether that's worth the fee depends on two things: whether you can use the deductions now, and how long you plan to hold the property.
• 100% bonus depreciation is permanent for qualifying property acquired after January 19, 2025, which makes the upside of a study larger than it has been in previous years.
• Passive loss limits and depreciation recapture at sale are the two factors most likely to turn a good-looking study into a poor investment.

Cost segregation gets pitched to almost every property owner who closes on a building. The pitch is usually some version of "you're leaving deductions on the table." Sometimes that's true. But a study costs real money, and for a meaningful share of investors the benefit is smaller than the sales conversation suggests.

The question that investors need to answer before commuting to a cost segregation study is whether a study will pay for itself on your specific property, given your income, your participation in your rentals, and your plans for the building. This article walks through how to answer that before you sign an engagement letter with a cost segregation firm.

What a Cost Segregation Study Actually Does

When you buy a rental property, from a tax perspective, the purchase price is split between land (which isn't depreciable) and the building. By default, the building is depreciated evenly over 27.5 years for residential rental property or 39 years for commercial property. Depreciation sits alongside the other rental property tax deductions you claim each year, and it's the one a cost segregation study changes.

A building is made up of many components, and not all of them fall into those long recovery periods. Examples include:

• 5- and 7-year property: certain carpeting, appliances, cabinetry, decorative lighting, and some dedicated electrical and plumbing serving specific equipment
• 15-year land improvements: paving, parking lots, sidewalks, landscaping, fencing, and site drainage
• 27.5- or 39-year property: the structural shell and components that serve the building generally, such as roofing, walls, and core HVAC

A cost segregation study is an engineering-based analysis that identifies which portion of your building's cost belongs in the shorter categories and documents the support for that allocation. It essentially breaks down the individual components of your building and allows you to take greater deductions in the early years of owning the asset.

The most important thing to understand about cost segregation is that it accelerates deductions. It doesn't create new ones. Your total depreciation over the life of the property is the same either way. The study pulls a portion of it into the early years of ownership.

Key Takeaway: Pulling deductions forward has real economic value. A dollar of tax saved this year can be reinvested, used to pay down debt, or applied toward your next acquisition, and a deduction taken in a high-income year may save more than the same deduction taken later. Every argument for or against a study comes back to how much that timing is worth to you.

Why Bonus Depreciation Changes the Math

On its own, reclassifying building costs into 5-, 7-, and 15-year property would speed up deductions modestly. What makes cost segregation especially powerful for real estate investors is bonus depreciation, which allows eligible property with a recovery period of 20 years or less to be deducted immediately rather than over its recovery period.

Under the 2017 Tax Cuts and Jobs Act, bonus depreciation was 100% but began phasing down in 2023: 80% that year, 60% in 2024, and 40% in 2025. The One, Big, Beautiful Bill Act reversed that. It permanently restored 100% bonus depreciation for qualified property acquired and placed in service after January 19, 2025. We covered the broader changes in our One Big Beautiful Bill overview.

Two details matter for investors:

• The acquisition date. Property is generally treated as acquired when a binding written contract is signed. A property under a binding contract on or before January 19, 2025 stays on the old phase-down schedule; properties acquired after that date are eligible for 100% bonus depreciation.
• State tax treatment may differ. Not every state follows federal bonus depreciation. New York has generally required taxpayers to add back federal bonus depreciation on most property, and Michigan decoupled from the restored 100% bonus rule in October 2025. The federal benefit of a study may be considerably larger than the state benefit.

To see how the pieces fit together, consider a hypothetical residential rental property purchased for $1.25 million in June 2026, with $250,000 allocated to land and $1 million to the building. The property is eligible for 100% bonus depreciation. Assume a study reclassifies 25% of the building cost into 5-, 7-, and 15-year property (actual reclassification percentages vary widely by property type, age, and construction). For simplicity, the figures below ignore the mid-month convention that applies in the first year.

That's roughly $241,000 in additional year-one deductions. For an investor in the 37% federal bracket who can fully use the loss, that translates to about $89,000 less federal tax in year one. But determining whether you can fully use this loss is important, and there are several other factors you should consider before scheduling a cost segregation study.

When a Cost Segregation Study Is Worth the Fee

Cost segregation tends to be clearly worthwhile when most of the following are true:

• You acquired or built the property recently, and the building basis is meaningful. The larger the depreciable basis, the more the benefit outweighs a largely fixed study fee.
• You can use the losses against other income. This is the big one, and it usually means one of three things applies:
• You qualify for real estate professional status and materially participate in your rentals, so rental losses aren't treated as passive.
• You own a short-term rental where the average guest stay is seven days or less and you materially participate, which in some cases takes the activity outside the passive rental rules.
• You have enough passive income from other rentals or investments to absorb the losses.
• You plan to hold the property for many years. A long hold gives you years of use from the accelerated deductions before any recapture at sale.
• You're in a high tax bracket now, but don’t expect to be in the future. Deductions are worth more at a 35% or 37% marginal rate than at 22% or 24%.

The profile where a study is closest to a no-brainer is an investor who qualifies as a real estate professional (or has a spouse who does), buys a property with substantial building basis, and intends to hold it for the long term. For that investor, a large year-one loss can offset wages, business income, or other nonpassive income in a high-rate year, and the time value of those savings compounds over a long hold.

Key Takeaway: Before you request a quote, talk to your accountant and make sure you understand the answer to one key question: if this study produced a large loss this year, could I actually deduct it? If the answer is no, the size of the projected deduction is close to irrelevant.

When a Cost Segregation Study Isn't Worth It

Cost segregation studies tend not to be worth it when the following is true:

• Small building basis. On a modest property, the dollar value of reclassified components may not be large enough for the tax savings to clearly outpace the fee of having the study conducted.
• Passive investors with no passive income to offset. Rental real estate is generally a passive activity, and under the IRS passive activity rules, passive losses that exceed passive income are disallowed for the year and carried forward. You cannot use passive losses to offset active income (like that from your W-2 job).
• You don’t plan on owning the property for long. This is where depreciation recapture comes in, and it deserves its own explanation.

When you sell a property for more than its depreciated basis, the IRS recaptures the depreciation you claimed. The portion attributable to the building itself is generally taxed at a maximum federal rate of 25%. The components a cost segregation study reclassifies as personal property are treated differently: depreciation on them is generally recaptured as ordinary income, to the extent of gain, at rates up to 37%. The rules for 15-year land improvements can be more complex. Our article on depreciation recapture planning covers the mechanics in more detail.

Go back to the hypothetical above. If that investor sells in year three, much of the $250,000 in bonus depreciation may come back as ordinary income. An investor who deducted it at 37% and recaptures it at 37% has gained roughly two years of deferral on the tax, minus the cost of the study. That's rarely a good trade.

A few other situations call for caution:

• Low current income, where the deductions would offset income taxed at low rates or produce a loss you carry forward anyway.
• Properties near the end of a planned hold, including look-back studies on buildings you expect to sell soon.
• Look-back studies on property acquired before January 20, 2025, which are generally limited to the bonus percentage in effect when the property was placed in service (80% for 2023, 60% for 2024) and to ordinary accelerated depreciation beyond that.

How to Evaluate a Study Before You Pay for One

A careful evaluation doesn't require committing to anything. Reputable cost segregation providers will typically offer a preliminary estimate of how much of your building's cost is likely to be reclassified, based on the property type, purchase price, and basic details about the building. Fees vary with property size, complexity, and the study approach, so get the fee in writing alongside the estimate.

With an estimate and a fee in hand, you can then work with your CPA to test the numbers against your actual situation:

1. Translate the estimate into usable tax savings. Apply your real marginal rate, then adjust for passive loss limits. A projected deduction you can't use this year is worth much less than its face value.
2. Account for state tax. Confirm whether your state follows federal bonus depreciation. For New York and Michigan investors, the state benefit may be minimal.
3. Model the exit. Estimate how much of the accelerated depreciation will be recaptured, and at what rate, based on your realistic hold period.
4. Compare the net benefit to the fee. What's left after those adjustments is what you're actually buying.

For properties already in service, a study isn't limited to the year of purchase. A look-back study generally lets you claim the depreciation you would have taken had the property been classified correctly from the start, through an automatic change in accounting method filed on Form 3115. The catch-up amount is generally taken in the current year without amending prior returns. That can make a look-back study attractive in a year when your income is unusually high, provided the passive loss and recapture analysis still supports it.

Run the Numbers Before You Buy the Study

Cost segregation is a well-established, IRS-recognized strategy, and with 100% bonus depreciation now permanent, the potential benefit on the right property is substantial. The investors who get the most from it share a few traits: they can deduct the losses when they arrive, they hold for the long term, and they're in a high bracket when the deductions land. For passive investors without passive income, owners of smaller properties, and anyone planning a near-term sale, the case is much weaker, and a study can cost more than it returns.

At Revonary, we help real estate investors evaluate whether a cost segregation study is worth it for their specific property and portfolio before they commit. We model the after-tax benefit against the fee, factoring in passive activity rules, state conformity, and your likely exit. When a study makes sense, we coordinate with a specialist to complete it and handle the tax treatment once it's done, as part of our broader tax planning services.

If you've recently acquired a property or you're weighing a pitch for a study right now, contact Revonary to run the numbers before you sign.