These two tax strategies are often confused, but they serve different purposes — and they're most powerful when used together.
Property owners frequently ask: "Should I do cost segregation or bonus depreciation?" The answer is that they're not competing strategies — cost segregation identifies the assets, and bonus depreciation accelerates the deduction. Understanding how they work together is key to maximizing your tax savings.
Cost segregation is an engineering-based study that reclassifies building components from the default 27.5-year (residential) or 39-year (commercial) depreciation schedule into shorter-lived asset categories (5, 7, or 15 years).
Bonus depreciation is a tax provision that allows you to deduct a large percentage of an asset's cost in the first year it's placed in service. It applies to assets with a recovery period of 20 years or less — which includes everything identified in a cost segregation study.
| Feature | Cost Segregation | Bonus Depreciation |
|---|---|---|
| What it does | Reclassifies building components into shorter depreciation categories | Allows first-year deduction of a percentage of asset cost |
| Applies to | Real property (buildings) | Personal property and land improvements (5, 7, 15-year assets) |
| Requires a study? | Yes — engineering-based analysis | No — but assets must be properly classified first |
| Current rate | N/A (it's a classification method) | Phasing down 20% per year from 100% (pre-2023) |
| Can apply retroactively? | Yes — look-back studies via Form 3115 | Yes — on newly reclassified assets from a look-back study |
Here's the critical point: without cost segregation, you can't take bonus depreciation on building components. By default, the IRS treats your entire building as a single 27.5-year or 39-year asset. Bonus depreciation only applies to assets with a 20-year or shorter recovery period.
Cost segregation is the mechanism that unlocks bonus depreciation for property owners. The study identifies which components qualify, and then bonus depreciation lets you accelerate the deduction into year one.
Example: You purchase a $2M commercial building. Without cost segregation, you depreciate $51,282 per year over 39 years. With a cost segregation study that reclassifies $600,000 into 5- and 15-year property, bonus depreciation lets you deduct a substantial portion of that $600,000 in year one.
Under the Tax Cuts and Jobs Act, bonus depreciation was 100% for assets placed in service through 2022. It's now phasing down by 20% per year. The current bonus depreciation schedule makes it increasingly important to act sooner rather than later.
If you own property, you almost certainly benefit from cost segregation. Whether bonus depreciation applies depends on when your assets were placed in service and the current rate. But even without full bonus depreciation, the accelerated depreciation schedules from cost segregation (5, 7, 15 years vs. 27.5 or 39 years) still deliver significant tax savings.
Read our complete cost segregation guide or learn about what a study costs.
At Crane Financial, we evaluate cost segregation and bonus depreciation as part of a broader tax strategy engagement. We'll model the exact savings for your specific property and tax situation.
Book a free review and we'll model how cost segregation and bonus depreciation could reduce your tax bill.
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