The question arrives in two forms. "I did a cost segregation study, will the exchange trigger all that recapture?" and "I just closed on a replacement property, can I run a study on it?" Both have clean answers, and both get answered badly, because the answer skips the distinction that decides everything: carryover basis versus excess basis.
The short answer
- In a fully deferred 1031 exchange, recapture on the real property portion of a prior study is deferred with the gain. The two strategies are partners, not competitors.
- Boot and unlike-property change the picture. Cash received, debt relief, or property that is not like-kind can force recognition, and §1245 assets sit in that zone.
- On a replacement property, carryover basis generally continues the old depreciation schedule. The excess basis, the new money above the relinquished property's value, is treated as newly acquired and is where the opportunity lives.
- An election can treat the entire replacement basis as placed in service in the exchange year, simplifying the schedule and broadening what a study reaches.
- Post-OBBBA, with 100% bonus depreciation permanent, the timing pressure is gone. You are no longer racing a phase-down.
Scenario 1: You Are Exchanging Out of a Property You Already Studied
Start with the fear, because it stops people from ordering studies at all. You accelerated $400,000 into 5- and 15-year property three years ago and are exchanging into a larger asset. Does the §1245 recapture come due?
In a fully deferred §1031 exchange, mostly no. Gain attributable to the real property, which includes land improvements and structural components, is deferred rather than recognized, and you carry the exposure forward into the replacement property instead of paying it. That is one of the strongest arguments for pairing the strategies. The exception is genuine personal property, covered below.
Two things demand attention. Boot first: cash taken at closing, or net debt relief, produces recognized gain, and recapture is generally the first thing that gain absorbs. Pull $150,000 out and it is not taxed at capital gain rates; it comes back as ordinary income first.
Second, unlike-property. Since 2017, §1031 applies to real property only. Land improvements and structural components qualify, but genuine tangible personal property a study identifies, appliances, carpet, furnishings, and cabinetry, does not, and disposing of it can trigger ordinary recapture in the exchange year. Which items fall on which side is a conversation for your CPA and qualified intermediary, held before the relinquished property closes. The framework is covered in §1245 versus §1250 property.
Scenario 2: You Are Acquiring Through a 1031 Exchange
This is where most of the money is, and where most owners are told the wrong thing.
Your basis splits in two. The carryover basis is the adjusted basis brought over from the relinquished property. It generally continues on its existing schedule, using the old recovery periods and remaining life, as though the property never changed.
The excess basis is the new money: the amount by which the replacement property's cost exceeds the value of what you gave up. That portion is treated as newly acquired property placed in service in the exchange year. It gets fresh recovery periods and is eligible for 100% bonus depreciation under §168(k), permanent after the One Big Beautiful Bill Act for property acquired and placed in service after January 19, 2025.
So: you can certainly cost segregate the excess basis, and how far a study reaches into carryover basis depends on the election below. If you traded up substantially, the excess basis alone can carry a study.
The Worked Example: $1.2M Carryover, $800,000 Excess
Example: trading a $2,600,000 property into a $3,400,000 replacement, closed in March The relinquished property has an adjusted basis of $1,200,000, which carries over. The additional $800,000 of purchase price is excess basis. Both figures are net of land allocation. A study on the excess basis reclassifies 28% into 5- and 15-year property. The structure line uses the MACRS mid-month convention, a 2.033% first-year factor for a March placement rather than a full 1/39.
| Excess basis, no study | Excess basis, with study | |
|---|---|---|
| Excess basis | $800,000 | $800,000 |
| Reclassified to 5- and 15-year | $0 | $224,000 |
| Remaining on 39-year structure | $800,000 | $576,000 |
| Year-one bonus depreciation | $0 | $224,000 |
| Year-one structure depreciation | $16,264 | $11,710 |
| Total year-one deduction | $16,264 | $235,710 |
| Additional deduction | $219,446 | |
| Cash value at a 35% combined rate | ~$76,800 |
The $1,200,000 carryover basis keeps running on its old schedule and contributes nothing new. The entire opportunity sits in the $800,000, producing roughly $76,800 against a study fee in the $5,000 to $15,000 range. Your result depends on your tax rate and whether you can use passive losses.
Scenario 3: Electing to Treat the Whole Basis as Newly Placed in Service
There is an alternative. Rather than maintaining two parallel schedules, an election is available to treat the entire replacement basis as placed in service in the exchange year.
The administrative appeal is obvious: one schedule instead of two, and one classification exercise. The analytical appeal is that a study can then reach the full basis rather than a slice.
The trade-off is real. Electing restarts the clock on carryover basis, so the structure depreciates over a fresh full recovery period rather than the shorter remaining life it had. And the bonus treatment of exchanged basis is a separate question from the treatment of excess basis; do not assume the whole amount picks up the 100% deduction. This is where a vendor's modeled projection will overstate your result. Our guide to bonus depreciation in 2026 covers the eligibility rules behind the answer.
The Honest Part: Powerful, and Genuinely Complex
Pairing cost segregation with a 1031 exchange is one of the most effective combinations available to a real estate owner. It is also where clean-looking projections most often fall apart. Three cautions.
Sequence matters, and so does the room. The exchange structure, the boot analysis, the basis split, and the depreciation election all interact. Your CPA and qualified intermediary need to be in the conversation together, before the relinquished property closes. A study commissioned afterward can only work with the basis the transaction produced.
Deferral is not elimination. Each exchange carries the accumulated recapture exposure into a larger asset, and the balance grows. It resolves one of two ways: a taxable sale, modeled in depreciation recapture after cost segregation, or death, where the §1014 step-up eliminates it for heirs. That is why exchange-and-hold pairs naturally with estate planning and the step-up in basis.
The post-OBBBA analysis has shifted. When bonus was phasing down toward zero, there was an argument for forcing transactions into a particular year. That pressure is gone, so structure the exchange for the economics of the deal, not the depreciation calendar. Timing still matters, just less urgently, and we cover it in when to order a study.
Frequently Asked Questions
Does a cost segregation study make a future 1031 exchange harder?
No, but it makes the asset detail schedule essential. The exchange and the eventual disposition are computed asset by asset, so the schedule has to stay current through the entire hold. Firms that deliver only a summary PDF create work at exactly the wrong moment.
Can I run a study on the replacement property years after the exchange?
Yes. A study can be performed on property placed in service in any prior year, with the catch-up handled through Form 3115 and a §481(a) adjustment taken in the year of change, and no amended returns. The exchange's basis structure still governs what the study can reach.
What if I received boot in the exchange?
Boot triggers recognized gain, and reclassified §1245 property means part of that gain is ordinary income rather than capital gain. It does not undo the exchange or the study, but it changes the tax on the cash you took out. Model it before closing.
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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.