Nothing else in the code lets a taxpayer deduct the cost of a 39-year building in year one. Section 168(n), created by the One Big Beautiful Bill Act, does exactly that for the nonresidential real property portion of a qualified production facility. Not the equipment. The shell itself.
For a client building a $40,000,000 plant, that changes the project's economics. It is also the provision most likely to be misapplied over the next three filing seasons, because the fences are narrow and the guidance interim.
Key takeaways
- §168(n) allows a 100% first-year deduction on the nonresidential real property portion of a qualified production facility, a real exception to the 39-year rule.
- The property must be used in a qualified production activity: manufacturing, production, or refining of tangible personal property, with substantial transformation.
- Construction must begin after January 19, 2025 and before January 1, 2029, and the property placed in service before January 1, 2031.
- Office, administrative, lodging, parking, sales, R&D, and software engineering space is excluded, making square-footage allocation the central engineering problem.
- Ceasing qualified production use within 10 years triggers recapture. A long-tail exposure, not a one-time filing decision.
What §168(n) Actually Allows
Under normal rules, a plant's shell is nonresidential real property recovered over 39 years. Bonus under §168(k) reaches property with a recovery period of 20 years or less, plus qualified improvement property, so the shell has always sat outside it.
Section 168(n) carves out an exception. Where a facility qualifies, the taxpayer may elect a 100% first-year deduction on the nonresidential real property portion used in the qualified production activity. The equipment inside was already reachable by bonus. This provision is about the building.
Treat it as a separate analysis from the 2026 bonus depreciation rules, with its own tests, election, and recapture rule. Our overview of the OBBBA depreciation changes puts the two in context.
The Qualified Production Activity Test
The activity must be the manufacturing, production, or refining of tangible personal property, and the process must effect a substantial transformation. That phrase does the filtering. Assembly that packages or combines components without changing the character of the article is a weaker case than a process converting inputs into a materially different product. A refinery qualifies. A steel fabricator cutting, forming, and welding raw stock into structural members qualifies. A distribution center receiving, storing, and shipping finished goods does not.
Two consequences. Mixed facilities are common, so a building doing light kitting on one side and real fabrication on the other needs an activity-by-activity look. And the analysis is factual, belonging in the file with process descriptions, equipment lists, and floor plans.
The Two Deadlines That Govern Everything
| Requirement | Threshold |
|---|---|
| Construction must begin | After January 19, 2025 |
| Construction must begin | Before January 1, 2029 |
| Property must be placed in service | Before January 1, 2031 |
Both ends matter. A project that broke ground in late 2024 falls outside the window. A 2028 groundbreaking on a plant with a long commissioning cycle risks the 2031 deadline.
For clients contemplating industrial construction, this is a scheduling input, not a tax footnote. The date construction begins is a documented fact, recorded contemporaneously with the ordinary new construction cost records.
The Excluded Space Types, and Why They Decide Your Number
Section 168(n) does not apply to space used for offices, administrative functions, lodging, parking, sales, research, or software engineering. In a real plant, that is never zero.
This is where the provision becomes an engineering exercise rather than a tax election. The question is not whether the building qualifies. It is how many square feet, and how many dollars, sit on each side of the line, and how you defend the split. IRS Notice 2026-16 supplies the interim framework for the election.
Why §168(n) Makes Cost Segregation More Important, Not Less
The intuition runs backward. If the building is fully deductible, why engineer anything? Because the deduction is not on the building. It is on the qualified portion, and someone must draw that boundary defensibly.
A study on a §168(n) facility does three things at once. It separates §1245 personal property and 15-year land improvements from the real property, since site work and parking are excluded anyway. It allocates the real property between qualified production and excluded space by square footage and cost, using floor plans and construction cost records under the detailed engineering methodology the IRS Cost Segregation Audit Techniques Guide calls most reliable. And it builds the documentation trail the ATG identifies as elements of a quality study: unit costs, asset groupings, engineering rationale, reconciliation to actual costs.
Nobody should move 8% of a $40,000,000 building across that line on a percentage assumption. Our guide for CPAs covers the workpaper handoff.
Worked Example: A $38,000,000 Fabrication Plant
Example: a $38M manufacturing facility placed in service in June 2027 Total cost $38,000,000. Land allocated at $3,000,000, leaving $35,000,000 of depreciable basis. Construction began March 2026. The process is metal forming and welding, a substantial transformation of raw stock.
| Component | Basis | Treatment | Year-one deduction |
|---|---|---|---|
| §1245 personal property (5- and 7-year) | $4,200,000 | 100% bonus | $4,200,000 |
| 15-year land improvements | $2,800,000 | 100% bonus | $2,800,000 |
| Real property, qualified production space (78%) | $21,840,000 | §168(n), 100% | $21,840,000 |
| Real property, excluded space (22%) | $6,160,000 | 39-year MACRS | $85,686 |
| Total | $35,000,000 | $28,925,686 |
Without the election, that $21,840,000 of qualified production real property would have produced about $303,800 of first-year depreciation on a 39-year life. The election adds roughly $21,536,000 of deduction, worth about $7,538,000 of deferred tax at 35%.
Now change one input. Shift the split from 78/22 to 70/30 and the year-one deduction falls by roughly $2,209,000. That sensitivity is the argument for engineering the allocation rather than estimating it. Your result depends on your tax rate and whether you can use passive losses.
Three Reasons to Be Careful With This Election
The guidance is interim. Notice 2026-16 supplies a framework, not a finished regulatory scheme. Real questions remain open: how far "substantial transformation" reaches into assembly and processing, how space serving both production and excluded functions is treated, and how the construction-begin date applies to phased projects. Telling a client that a marginal facility clearly qualifies is not defensible today.
The 10-year recapture rule is a real exposure. If the property ceases qualified production use within 10 years, recapture applies. A plant sold, converted to warehousing, or idled inside that window can reverse a very large deduction. Put that in the client conversation before the election, in writing.
The election is not costless. It requires the qualification analysis, a defensible allocation, and ongoing monitoring. Facilities that mostly warehouse and lightly process are where examiners will look first. For those buildings, standard industrial and warehouse cost segregation remains the right tool.
Frequently Asked Questions
Does a warehouse or distribution center qualify?
Generally no. The statute requires manufacturing, production, or refining with substantial transformation. Storage, sorting, picking, and shipping transform nothing. A distribution center with an incidental production line requires an allocation, and the production portion must stand on its own facts.
Does §168(n) replace the need for a cost segregation study?
No, it increases it. The election applies only to the qualified production portion, so the study performs both the §1245 and land improvement separation and the square-footage allocation that sizes the deduction.
What happens if the plant is sold within 10 years?
Ceasing qualified production use within 10 years triggers recapture. The mechanics depend on the transaction and the guidance in effect, which is why hold-period expectations belong in the decision to elect.
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This article is provided by Precision Cost Segregation for general educational purposes and does not constitute tax, legal, or accounting advice. Tax outcomes depend on your specific facts, your tax rate, your passive activity position, and your entity structure. Figures shown are illustrative. Consult your CPA or tax advisor before acting, and engage a qualified professional to perform any cost segregation study. Information is current as of publication.
This article is general information, not tax or legal advice. Depreciation outcomes depend on your facts, elections, and current law — consult your CPA before acting. © 2026 Precision Cost Segregation.