100% Bonus Depreciation Is Back: What Real Estate Owners Should Review in 2026
The headline is simple: 100% bonus depreciation is permanent again. The application to your building is not simple at all. Before that number shows up on a projection or a pro forma, it is worth understanding exactly what qualifies, what doesn’t, and where the analysis actually happens.
“100%” describes the rate. It does not describe the building.
A real estate owner deciding whether this rule applies to a recent or upcoming acquisition needs four things confirmed before treating any number as real.
What Changed With Bonus Depreciation
For several years, bonus depreciation was on a scheduled phase-down: 100% for property placed in service through 2022, then stepping down in increments — 80%, 60%, 40% — toward zero by 2027. Real estate owners who ran the numbers on a cost segregation study in, say, 2024 were working against a shrinking percentage, which made the timing of an acquisition or a study part of the math itself.
Current IRS guidance reflects a change to that schedule: permanent 100% additional first-year depreciation generally applies to qualified property acquired after January 19, 2025. The phase-down is no longer the constraint it was. That is a meaningful shift for anyone planning a purchase, a renovation, or a cost segregation study going forward, because the percentage is no longer sliding under the analysis as the calendar moves.
What has not changed is the underlying structure of the rule. Bonus depreciation was never a deduction against the full purchase price of a building. It has always applied to specific categories of property within a building — the categories just now qualify at 100% instead of a reduced rate, for property that meets the acquisition-date test.
Why “100%” Does Not Mean 100% of Every Building
This is the point where the headline and the actual deduction tend to part ways. A commercial or residential rental building is generally depreciated over 39 or 27.5 years under standard rules, because the structure itself — the shell, the foundation, the roof system, the core building components — does not qualify for bonus depreciation. Bonus depreciation applies to property with a recovery period of 20 years or less: things like certain personal property, land improvements, and specific building components identified through engineering analysis.
| Category | Typical Treatment | Why |
|---|---|---|
| Building structure | 39-year or 27.5-year depreciation, not bonus-eligible | Recovery period exceeds the 20-year threshold for bonus property. |
| Land improvements | Often 15-year property, potentially bonus-eligible | Falls within the recovery-period window when properly classified. |
| Certain interior components, fixtures, specialty systems | Often 5- or 7-year property, potentially bonus-eligible | Classified separately from the building shell when supported by engineering analysis. |
| Land itself | Never depreciable | Land is not a depreciable asset under any method. |
The result is that even at a 100% rate, bonus depreciation typically applies to a portion of a property’s total basis — often a meaningful portion, but rarely the whole purchase price. Treating “100% bonus depreciation” as shorthand for “write off the whole building this year” is the single most common misapplication of this rule, and it is exactly the kind of assumption that draws scrutiny if it appears on a return without the analysis behind it.
Where Cost Segregation Enters the Analysis
A cost segregation study is the engineering-based process that identifies which components of a property qualify for shorter recovery periods in the first place. Without one, a building is typically depreciated as a single asset over its full 39- or 27.5-year life, and the components that would otherwise qualify for bonus treatment stay embedded in that long schedule by default.
A qualified specialist reviews the property.
Engineering-based cost segregation studies are performed by specialists trained to identify and support the classification of individual building components — not estimated from a spreadsheet template.
Components are classified by recovery period.
Each identified component is assigned to its correct depreciation category based on IRS guidance and established case law, with documentation to support that classification if it is ever reviewed.
Your CPA or EA applies the result to your return.
The study’s findings are incorporated into the depreciation schedule your tax preparer files — the study identifies the numbers; your CPA or EA is responsible for how they’re reported.
Not every property justifies the cost of a study. Smaller acquisitions, properties with limited qualifying components, or holdings already near the end of their planning horizon may not see enough benefit to offset the study’s cost. This is a threshold question worth asking before ordering one, not after.
Acquisition Date Versus Placed-in-Service Date
Two dates matter for bonus depreciation eligibility, and they are not interchangeable. The acquisition date is generally when a binding contract to acquire the property was entered into, or when the property was otherwise acquired under applicable rules — this is the date tested against the January 19, 2025 threshold for the permanent 100% rate. The placed-in-service date is when the property is actually ready and available for its intended use, which can come well after acquisition for a renovation, a build-out, or a property held before being put into service.
Acquired before, placed in service after
A property under contract before the threshold date but not placed in service until later requires a closer look at which date controls eligibility under the applicable transition rules.
Acquired and placed in service in the same year
The more straightforward case, but still requires confirming the acquisition date falls after January 19, 2025 for the permanent 100% rate to apply.
Self-constructed property
Different rules can apply to property a taxpayer manufactures, constructs, or produces themselves, where construction may span the threshold date.
Getting these dates confused is a common source of overstated deductions — a purchase agreement signed months before the effective threshold does not automatically become eligible just because the closing or the placed-in-service date happened to land later. This is precisely the kind of fact pattern where a documented timeline, reviewed with your CPA or EA, replaces a guess.
How Depreciation Affects the Broader Tax Picture
Bonus depreciation does not exist in isolation from the rest of a real estate owner’s tax position. A large first-year deduction can generate a loss that interacts with passive activity loss rules, at-risk limitations, and — for owners who qualify as real estate professionals — different treatment than for passive investors. The size of the deduction is only half the analysis; what happens to that deduction once it reaches your return is the other half.
The operating principle: a bonus depreciation deduction is only as useful as the tax position it lands in. The same dollar amount can behave very differently depending on passive activity status, entity structure, and what other income or losses exist in the same year.
This is also where timing decisions belong in a broader conversation rather than a standalone one. Accelerating depreciation into a single year has consequences for future years’ taxable income on the same property, for eventual depreciation recapture on sale, and for how the deduction interacts with any other planning already underway. None of that changes whether the rule applies — it changes whether taking full advantage of it, in a given year, is the right call for your overall position.
Questions to Answer Before Ordering a Study or Filing
Before treating 100% bonus depreciation as a number on a projection, a short list of questions tends to separate a supportable deduction from an assumption that won’t hold up under review.
Source framework
This guide reflects current guidance from the IRS newsroom announcement on the additional first-year depreciation deduction and IRS Publication 946, along with current Treasury guidance. Eligibility for a specific property should be confirmed with a qualified cost segregation specialist and reviewed with your CPA or EA before filing.
Frequently Asked Questions
Does 100% bonus depreciation mean I can deduct the full price of a building in year one?
No. It means eligible components of the property — not the structure itself — can be depreciated at a 100% rate in the year they’re placed in service, once identified through a cost segregation study. The building shell is still depreciated over its standard 39- or 27.5-year life.
Do I need a cost segregation study to claim bonus depreciation?
In practice, yes, for most owners to identify what actually qualifies. Without a study, a property is generally depreciated as a single asset, and the components eligible for shorter recovery periods stay inside that longer schedule by default.
What if my property was under contract before January 19, 2025 but closed after?
This is a fact-specific question about which date controls under the applicable transition rules, and it’s exactly the kind of scenario worth reviewing with your CPA or EA and a cost segregation specialist before assuming either date applies.
Is this the same as a Section 1031 exchange or other real estate tax strategy?
No. Bonus depreciation is a separate mechanism from a like-kind exchange, and the two can interact in ways that affect basis and future depreciation. They should be evaluated together as part of your overall plan, not treated as interchangeable tools.
Before assuming an acquisition or improvement qualifies, have Slate & Summit map the facts and coordinate the question with the appropriate CPA/EA.
Bring the acquisition documents, the placed-in-service timeline, and your current depreciation schedule. We’ll help identify what warrants a closer look before it becomes a filing position.
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