Cost segregation is the most-pitched tax strategy in real estate, and the pitch usually skips the parts that matter: whether you can actually use the deduction, what the study costs against the benefit, and what happens when you sell. Here is the full picture.
What a study does
When you buy a building, the default is to depreciate the whole purchase price (less land) over 27.5 years for residential rental property or 39 years for nonresidential property under Section 168. A cost segregation study breaks the building into its components and assigns each to its proper recovery period. Carpet, cabinetry, specialty electrical, and equipment are 5- or 7-year property. Parking lots, landscaping, fencing, and site utilities are 15-year land improvements. The structure, roof, and core systems stay at 27.5 or 39 years.
The shorter-lived components then qualify for bonus depreciation under Section 168(k), at whatever percentage is in effect for the year the property is placed in service, which Congress has changed several times. The result is that a large share of the purchase price, often 20 to 35 percent for a typical building and more for restaurants, medical offices, and manufacturing space, can be deducted in the first year instead of over three or four decades.
The deduction is a timing benefit. Total depreciation over the life of the building does not change. What changes is when you take it, and the value of that is the tax deferred and the use of the money in the meantime.
Who benefits
Three questions decide whether a study is worth doing.
Can you use the loss? Rental losses are passive under Section 469. Unless you qualify as a real estate professional, run a short-term rental you materially participate in, or have other passive income to offset, a first-year loss from cost segregation may simply be suspended and carried forward. A suspended loss still has value, but the marketing that promises a refund check assumes you can use the loss this year.
Is the basis large enough? Study fees do not scale down much with the size of the property, so the ratio of fee to benefit improves as the basis grows. A single small rental rarely justifies an engineering study. A portfolio, a commercial building, or a large multifamily property usually does.
How long will you hold it? The longer you hold, the longer the deferral works for you. A property you plan to sell in two years gives back much of the benefit through recapture, discussed below.
Studies can also be done on property you already own. A lookback study uses Form 3115 to change the accounting method, and the catch-up depreciation is taken in the current year under Section 481(a) without amending prior returns.
What a study costs relative to the tax effect
An engineering-based study, where someone walks the property and assigns costs from construction records and industry data, runs from the low thousands for a simple property into five figures for a large or complex one. The benefit is easy to estimate before you commit: reclassified basis, times the bonus percentage in effect, times your marginal federal and state rate, gives the first-year tax deferred. Any reputable provider will give you that estimate for free before you engage them. If the estimated first-year deferral is not several multiples of the fee, or you cannot use the loss this year, wait.
Two cautions. Cheaper software-only studies with no site visit have been challenged on audit, and the IRS Cost Segregation Audit Techniques Guide lays out what examiners expect to see in a report. And New York and New Jersey do not follow the federal bonus rules in full, so the state benefit is usually smaller and the state depreciation schedule runs separately.
Recapture on sale
When you sell, the depreciation you took comes back in two forms:
- Section 1245 recapture on the 5- and 7-year components. Depreciation taken on these is taxed as ordinary income at your regular rate, up to the amount of gain.
- Unrecaptured Section 1250 gain on the building and land improvements. Straight-line depreciation on these is taxed at a maximum rate of 25 percent, above the usual long-term capital gains rate.
The rest of the gain is long-term capital gain. So a study converts some future capital gain into future ordinary income, in exchange for a deduction today. On a long hold, the deferral usually outweighs the rate difference. On a short hold, it may not. A 1031 exchange defers the recapture along with the rest of the gain, and holding until death eliminates it through the basis step-up, which is why cost segregation pairs so often with an exchange or a long-term family hold.