Order Cost Segregation at 100% Bonus Depreciation 2026

Bonus depreciation went back to 100% for any property placed in service after January 19, 2025 under the One Big Beautiful Bill Act. If you own a rental and haven't ordered a cost segregation study yet, the math changed in your favor and the window to act is now.

Why this matters

Bonus depreciation dropped to 80% in 2023, 60% in 2024, and 40% for early 2025 acquisitions. OBBBA reversed that phase-down entirely. Property acquired and placed in service after January 19, 2025 now depreciates reclassified components at 100% in year one.

That single change is the difference between spreading a deduction across 15 years and taking the whole thing this tax season. For a short-term rental owner in the 37% bracket, a $46,250 tax savings this year beats the same $46,250 trickled out over a decade and a half.

Cost segregation is what makes that 100% rate usable. Without a study, your building sits on a 27.5-year (residential) or 39-year (if misclassified) depreciation schedule with almost nothing eligible for bonus treatment. A study reclassifies 20-45% of the property's value into 5, 7, and 15-year buckets that qualify.

What you'll need

• The property's purchase price, closing statement, and land-to-building value split
• Confirmation the property is residential rental, Airbnb, VRBO, or short-term rental (not commercial)
• The placed-in-service date, since anything after January 19, 2025 gets the full 100% rate
• Prior year depreciation schedule if the property has been in service for more than one year
• Your CPA's contact info, since the cost segregation study is implemented on their end, not filed by the provider
• 3-5 business days of turnaround time to receive the report before your filing deadline

The steps

1. Confirm the placed-in-service date

This single date decides your bonus depreciation rate. Property placed in service on or before January 19, 2025 falls under the old phase-down schedule. Property placed in service after that date qualifies for the full 100% rate restored by OBBBA.

Check your closing documents or the date you first listed the unit on Airbnb or VRBO. Getting this wrong means recalculating your entire deduction later. Common mistake: confusing the purchase date with the placed-in-service date. A property bought in December 2025 but not rented until January 2026 uses the later date.

2. Estimate your reclassification potential before ordering

Most residential rental and short-term rental studies reclassify 20-45% of the depreciable basis into shorter-life categories. Land improvements, appliances, flooring, and certain electrical and plumbing components typically qualify.

Run a manual savings estimate first. On a $500,000 property with 25% reclassified, that's $125,000 moved into bonus-eligible categories. At the 100% rate, the full $125,000 becomes a 2026 deduction instead of a number spread across three decades.

3. Order the engineering-based study

A desktop or virtual study doesn't require a site visit for most residential properties, which keeps turnaround at 3-5 business days instead of the weeks a site-visit firm takes. Virtual Cost Segregation runs a flat $2,200 fee with no per-property upsells for cost segregation for Airbnb and short-term rentals.

Avoid overseas contractors or bargain-bin providers advertising sub-$500 studies. A study that skips engineering documentation won't hold up if the IRS asks for support, and the whole point of the report is that it's audit-defensible.

4. Hand the report to your CPA before filing

The report itself is not filed with the IRS. It's a 100+ page supplementary document your CPA uses to prepare the actual tax return, whether that's a current-year return or an amended one.

For a property placed in service in 2026, the deduction flows straight into this year's return. For a property placed in service in a prior year that never got a study, your CPA files a Form 3115 to catch up the missed depreciation without amending prior returns.

5. Apply the deduction against W-2 or active income if you qualify

A cost segregation deduction only offsets W-2 income directly if you meet the short-term rental loophole tests, average stays of seven days or less and material participation. Otherwise the loss is passive and offsets passive income first.

Check material participation requirements before assuming the deduction wipes out your day-job tax bill. This is the step most new investors skip, and it's the reason some studies produce a paper loss that sits unused for years.

6. File and keep the documentation

Once your CPA files the return with the reclassified depreciation schedule, keep the full study report, the time logs if you're claiming the STR loophole, and your placed-in-service documentation together. Audit defense support only works if the paperwork is organized before an inquiry ever shows up.

Common mistake: treating the study report as optional backup instead of the primary support document. Examiners reviewing accelerated depreciation ask for the engineering study first.

Troubleshooting

My property was placed in service before January 19, 2025. You still qualify for a study, just at a lower bonus rate for the pre-2025 portion. Newer components or renovations added after that date can still hit the 100% rate.

I've owned the property for five years and never did a study. You don't need to amend past returns. A look-back study combined with Form 3115 catches up the missed depreciation as a single adjustment in the current year. See how to catch up missed depreciation with Form 3115.

My CPA says the deduction is passive and can't offset my W-2 income. That's correct unless you meet the short-term rental loophole tests. Review the average rental period and material participation rules before ordering if offsetting W-2 income is the goal.

I refinanced or sold part of the property recently. A cash-out refinance doesn't trigger a new study requirement on its own, but a sale or 1031 exchange changes the basis calculation. Loop in your CPA before the study is finalized, not after.

The study reclassified less than I expected. Reclassification percentage depends heavily on property type, finish level, and land value ratio. A bare-bones rental reclassifies less than a fully furnished short-term rental with high-end appliances and outdoor amenities.

Tools and resources

• 100% bonus depreciation and cost segregation for 2026
• OBBBA bonus depreciation rules for rental property
• How to know if your property qualifies for cost segregation
• Your CPA or tax preparer, who implements the study's findings on the actual return
• A manual savings estimate, useful for sizing expectations before you commit to a study

What to do next

If your property is a long-term rental instead of a short-term one, the numbers still work but the offset rules differ. Compare the two paths in STR loophole vs long-term rental savings before deciding which strategy fits your income situation.

FAQ

One last thing

The 100% rate isn't permanent by design, it's tied to the placed-in-service date under current law, which means timing matters more this year than in any year since bonus depreciation started phasing down in 2023. A property that sits without a study through 2026 doesn't lose eligibility, but every year you wait is a year of depreciation you could have accelerated instead of stretched across three decades.

Related guides

• How to combine cost segregation with a 1031 exchange
• Average tax savings from the STR loophole
• How to read a cost segregation study report
• Using cost segregation on a property you've owned for years