What it does
A building acquired as a single asset is depreciated over a long recovery period. In reality it is an assembly of components with different useful lives: the structure itself, and within it the carpeting, specialty electrical, cabinetry, decorative fixtures, and separately the land improvements outside.
An engineering-based cost segregation study allocates the purchase price among those components. The portions properly classified as personal property or land improvements carry much shorter recovery periods, and where bonus depreciation is available they can frequently be deducted immediately.
The result is a substantial deduction pulled into the early years of ownership. That is the product, and it is real.
What it does not do
Four limitations decide whether the study is worth commissioning, and none of them is a criticism of the study itself.
- 01It does not create a deduction. Total depreciation over the life of the asset is unchanged. The study alters timing. Its value is the time value of the acceleration, plus any rate arbitrage between the year of the deduction and the years it was taken from, and nothing more.
- 02It does not make the loss usable. Depreciation on a rental generates a passive loss, and a passive loss cannot offset wages or portfolio income. Without material participation, or without the short-term rental position, the accelerated deduction sits on the form and waits.
- 03It does not override the at-risk rules or the excess business loss limitation. A loss that clears the passive hurdle can still be deferred by either.
- 04It does not survive the sale. The acceleration is reversed on disposition, and the character of the reversal is worse than the character of the gain it offset.
When the arithmetic works
Stated as a question the study cannot answer for you: is the acceleration worth more than the recapture, given how long the property will actually be held and what the owner's rate will be in each of those years?
| Fact | Effect on the case for a study |
|---|---|
| Long intended hold | Strengthens it. The deferral compounds and recapture is distant |
| Sale expected within a few years | Weakens it considerably. Recapture arrives before the deferral has earned anything |
| Owner materially participates, or the property is short-term rental | Strengthens it. The loss is usable against other income now |
| Owner is passive with no other passive income | Weakens it. The deduction is suspended and the study has bought timing that has not begun |
| Current-year rate unusually high | Strengthens it. The rate arbitrage is real |
| Exchange or estate planned on exit | Changes the analysis materially and should be modeled before commissioning |
Doing it late
A study can generally be performed on a property acquired in an earlier year, with the cumulative difference between the depreciation taken and the depreciation that should have been taken claimed in the current year through a change in accounting method, without amending prior returns.
This is a genuinely useful provision and it is frequently the best version of the exercise, because the owner is choosing the year in which to take the catch-up rather than having it fall where the acquisition happened to land.
One caution belongs with it. The quality of the study is the whole of the defense. An engineering-based study with a detailed component analysis and supporting documentation is a different exhibit from a percentage applied to a purchase price by someone who never visited the property.
General information only. This article describes law and practice as we understand them at the time of writing. It is not tax, legal, accounting, or investment advice, it does not consider your circumstances, and it does not create an advisor-client or attorney-client relationship. Odyssey Strategic Advisors LLC is not a law firm and is not a CPA firm. Confirm any position with your own tax professional before acting on it. See our disclosures.