The passage of the Big Beautiful Bill in 2025 restored 100% bonus depreciation for real estate investors. This change reignited a common question: Should I use bonus depreciation or Section 179 to accelerate my deductions?
Both provisions allow taxpayers to deduct the cost of qualifying property in the year it is placed in service. However, they differ in important ways. Eligibility rules, dollar limits, income restrictions, and qualifying property types vary significantly between the two.
For most real estate investors, bonus depreciation provides substantially greater benefits than Section 179. The qualifying property rules for Section 179 exclude many assets commonly identified through cost segregation studies. This guide compares both strategies side by side and explains when each applies.
Important note: The 100% bonus depreciation rate applies only to property acquired after January 19, 2025. If you signed a written binding contract before January 20, 2025, your property remains subject to the 40% phase-down rate regardless of when it is placed in service.
Bonus Depreciation: The Unlimited First-Year Deduction
Bonus depreciation allows taxpayers to deduct a specified percentage of qualifying property costs in the year the asset is placed in service. Following the Big Beautiful Bill, that percentage is now 100% for property acquired after January 19, 2025.
Key features include:
- No dollar limit on the total deduction amount
- No taxable income requirement. Bonus depreciation can create a Net Operating Loss (NOL)
- Applies automatically unless the taxpayer elects out on a class-by-class basis
- Available for both new and used property
Qualifying property includes:
- MACRS property with a recovery period of 20 years or less
- Qualified Improvement Property (QIP) with a 15-year recovery period
- Land improvements such as parking lots, sidewalks, and landscaping (15-year property)
- Tangible personal property, including specialty electrical, carpeting, and decorative finishes, identified through cost segregation services
Can I claim bonus depreciation on used property?
Yes. Since the Tax Cuts and Jobs Act of 2017, used property qualifies for bonus depreciation. The asset must be new to the taxpayer and meet specific acquisition requirements. The taxpayer cannot have held a depreciable interest in the property within the previous five calendar years.
Section 179: The Elective Expense Deduction
Section 179 allows taxpayers to elect to deduct the cost of qualifying property in the year it is placed in service. Unlike bonus depreciation, this deduction requires an affirmative election on the tax return.
2025 limits:
- Maximum deduction: $1,250,000
- Phase-out threshold: $3,130,000. The deduction reduces dollar-for-dollar for purchases above this amount
- SUV limit: $31,300
Qualifying property includes:
- Tangible personal property, such as machinery, equipment, and furniture
- Off-the-shelf computer software
- Qualified real property limited to HVAC systems, roofs, fire protection, and security systems for nonresidential buildings
What does NOT qualify for Section 179:
- Land and land improvements, including parking lots, sidewalks, landscaping, and fences
- Property used predominantly outside the United States
- Property leased to others by non-corporate lessors (with limited exceptions)
This distinction is critical for real estate investors. Many assets identified through a cost segregation study are land improvements. These items qualify for bonus depreciation but not Section 179.
Critical limitation:
Section 179 deductions cannot exceed taxable income from the active conduct of a trade or business. This restriction applies regardless of whether an investor holds Real Estate Professional Status.
Can Section 179 create a tax loss?
No. Unlike bonus depreciation, Section 179 is limited to your taxable business income. Any disallowed amount carries forward to future tax years indefinitely.
Bonus Depreciation vs. Section 179: Key Differences at a Glance
The following table summarizes the primary distinctions between these two accelerated depreciation methods.
Key takeaway for real estate investors: Most assets identified through cost segregation studies qualify for bonus depreciation but not Section 179. This makes bonus depreciation the primary accelerated depreciation tool for rental property owners.
Real Numbers: How a $2 Million Property Purchase Plays Out
Consider a real estate investor who purchases a $2,000,000 commercial property in 2025. A cost segregation study identifies $500,000 in assets eligible for accelerated depreciation. The remaining value is allocated to the building structure and land value, which is not depreciable.
The $500,000 breaks down as follows:
- $350,000 in land improvements (parking lot, landscaping, site lighting)
- $100,000 in tangible personal property (carpet, decorative fixtures, specialty electrical)
- $50,000 in qualified real property (HVAC system, fire suppression)
Bonus depreciation application:
- All $500,000 qualifies for 100% bonus depreciation
- Year 1 deduction: $500,000
- At the 37% tax bracket, this equals $185,000 in tax savings
Section 179 application:
- Only $150,000 qualifies ($100,000 personal property + $50,000 qualified real property)
- Land improvements ($350,000) are excluded
- If business taxable income is $150,000, Section 179 is capped at $150,000
Key insight: For this commercial property, bonus depreciation delivers more than three times the potential deduction compared to Section 179. The land improvements identified through cost segregation represent the largest category of accelerated assets, and these do not qualify for Section 179.
Choosing the Right Deduction: 5 Factors to Consider
1. Your Property Type
Real estate investors almost always benefit more from bonus depreciation. Section 179 excludes land improvements, which typically represent the largest portion of cost segregation savings. Investors utilizing the STR loophole with short-term rentals should focus on bonus depreciation paired with cost segregation.
2. Your Taxable Income Level
Low or negative income favors bonus depreciation. It can create an NOL to carry forward to future years. Section 179 requires sufficient business income to absorb the deduction.
Note that bonus depreciation may create passive losses that are limited unless you qualify as a Real Estate Professional or meet other material participation exceptions.
3. Investment Size
Placing more than $3.13 million in assets into service triggers the Section 179 phase-out. Bonus depreciation has no such limitation.
4. State Tax Conformity
Many states decouple from federal bonus depreciation rules. California, New York, and New Jersey are notable examples. Check your state's conformity before finalizing your strategy.
5. Future Tax Planning
Expecting higher income next year? You may elect out of bonus depreciation to preserve deductions. This election is made on a class-by-class basis and must be made on a timely filed return.
Planning a 1031 exchange? Coordinate your depreciation strategy with your exit timeline.
Can I use both bonus depreciation and Section 179 on the same property?
Yes. The IRS requires you to apply them in a specific order. First, apply Section 179 to your elected amount. Then apply bonus depreciation to the remaining basis. Finally, use regular MACRS depreciation on any leftover value. This order is mandatory under the regulations.
Unlocking Hidden Deductions with a Cost Segregation Study
Both bonus depreciation and Section 179 can deliver greater value when paired with a cost segregation study. However, the primary benefit for real estate investors flows through bonus depreciation.
A cost segregation study is an engineering-based analysis that reclassifies building components into shorter recovery periods. Carpeting, specialty lighting, parking lots, and landscaping often qualify for 5-, 7-, or 15-year depreciation instead of 27.5 or 39 years.
Typical results identify 20-40% of building costs eligible for accelerated treatment. The majority of these assets are land improvements and tangible personal property that qualify for bonus depreciation.
Combined with 100% bonus depreciation, investors often write off hundreds of thousands of dollars in Year 1.
Does cost segregation work for properties I have owned for years?
Yes. A look-back study allows you to catch up on missed depreciation in a single year. This requires filing Form 3115 with your tax return. No amended returns are necessary.
Quality studies include site visits to document and photograph property components. This documentation strengthens IRS audit defense and ensures accurate asset classification.
Making the Right Choice for Your Investment
For real estate investors, the choice between bonus depreciation and Section 179 is often straightforward. Bonus depreciation applies to a broader range of assets, has no income limitation, and includes the land improvements that represent the largest category of cost segregation savings.
Section 179 has a narrower role. It may apply to specific interior improvements in commercial buildings, such as HVAC systems, roofs, and fire protection. For business equipment purchases outside of real estate, Section 179 provides control over exactly which assets receive accelerated treatment.
The most effective strategy combines cost segregation with 100% bonus depreciation. This approach maximizes Year 1 deductions and accelerates tax savings for rental property owners.
R.E. Cost Seg specializes in engineering-based cost segregation studies that maximize your bonus depreciation benefits. Our team identifies every eligible asset and provides IRS-defensible documentation.
