This article is provided for educational and informational purposes only. It does not constitute legal, financial, or tax advice, and no attorney-client relationship is formed by reading it. Laws, regulations, official guidance, and related information vary by jurisdiction, change frequently, and may have changed or become outdated since the publication date. Always verify current information with authoritative sources and consult a qualified professional about your specific circumstances. The author and publisher assume no liability for actions taken based on this information.
- 2020 bonus depreciation was an accelerated federal deduction
- Acquired and placed in service describe different events
- Qualified property was a defined category, not a synonym for business property
- The CARES Act changed qualified improvement property retroactively
- The allowance was generally automatic unless a class election changed it
- Bonus depreciation changed timing, basis, and later-year deductions
- Federal eligibility did not guarantee matching state treatment
- The current 2026 rule is different from a simple continuation of 2020 law
- A 2020 record must be read as a collection of facts
- Sources
Key Facts
- Federal level: For most qualified property acquired after September 27, 2017, and placed in service during 2020, federal bonus depreciation generally used a 100% additional first-year deduction.
- Federal level: Bonus depreciation accelerated an otherwise available depreciation deduction; it was not a tax credit and did not make every business purchase deductible.
- Federal level: The 2020 rules could cover qualifying new property and certain qualifying used property, but statutory eligibility conditions and exclusions still applied.
- Federal level: The CARES Act assigned qualified improvement property a 15-year recovery period under the general depreciation system, retroactively correcting a problem that had prevented much of that property from qualifying for bonus depreciation.
- Federal level: Federal law permitted an election out of bonus depreciation for a class of qualified property placed in service during the tax year; the election was not an item-by-item choice within that class.
- Federal level: Acquisition date, placed-in-service date, recovery period, business use, prior ownership, and other elections could change whether the 2020 allowance applied.
- Federal level: The rules in force in 2026 are not simply the old phase-down continued forward: legislation enacted in 2025 restored a permanent 100% federal allowance for qualifying property acquired and placed in service after January 19, 2025.
- Federal and state: Section 168(k) governs the federal deduction; it does not by itself establish whether a state income-tax system conforms to the same treatment.
2020 bonus depreciation was an accelerated federal deduction
In 2020, “bonus depreciation” was the common name for the additional first-year depreciation deduction in Section 168(k) of the Internal Revenue Code. Depreciation normally spreads the cost of qualifying business or income-producing property across a recovery period. Bonus depreciation moved more of that deduction into the year the property was first placed in service.
For most qualified property acquired after September 27, 2017, and placed in service before January 1, 2023, the applicable federal percentage was 100%. That timing rule covered qualifying property placed in service during 2020, subject to the statute, Treasury regulations, and any relevant elections.
The word “100%” is easy to misunderstand. It described the percentage of eligible depreciable basis that could receive the additional first-year deduction. It did not mean that every purchase qualified, that the government reimbursed the purchase price, or that a deduction produced a dollar-for-dollar reduction in tax.
Acquired and placed in service describe different events
The 2020 framework depended on more than the date printed on an invoice. Federal depreciation law distinguishes acquiring property from placing it in service. Property is generally placed in service when it is ready and available for its assigned use, even if the business does not operate it continuously from that moment.
This distinction can separate two transactions that look similar. Equipment might be ordered or purchased in one period but installed and ready for use in another. Self-constructed property and property acquired under a written binding contract can raise additional timing questions. The historical rules therefore cannot be reconstructed from the label “2020 purchase” alone.
Qualified property was a defined category, not a synonym for business property
The 100% rate applied only to qualified property. The 2020 materials included several important categories, most notably depreciable property with a recovery period of 20 years or less under the modified accelerated cost recovery system. Certain computer software, water utility property, qualified film, television, and live theatrical productions, and qualifying plants could also fall within Section 168(k).
Land was not depreciable, and a building generally did not become short-lived qualified property merely because a business used it. Certain components or improvements could have a different classification from the larger building. Special exclusions also applied to specified utility property, some property connected to businesses using particular interest-limitation elections, and property subject to other statutory restrictions.
The Tax Cuts and Jobs Act also expanded the allowance to certain used depreciable property. That expansion did not make every secondhand asset eligible. The rules included limits involving prior use by the same taxpayer, related-party acquisitions, carryover basis, and other nonrecognition transactions.
The CARES Act changed qualified improvement property retroactively
Qualified improvement property, often shortened to QIP, generally concerns certain improvements to the interior of an existing nonresidential building. Enlargements, elevators and escalators, and changes to a building’s internal structural framework are excluded from that definition.
The 2017 tax legislation intended significant changes for this type of property but left it without the 15-year classification needed for much of it to fit within the bonus-depreciation rules. Section 2307 of the CARES Act corrected that problem in 2020. It classified qualified improvement property as 15-year property under the general depreciation system and made the correction effective as if it had been included in the 2017 legislation.
As a result, qualifying improvements placed in service after 2017 could become eligible for the additional first-year deduction if the other Section 168(k) requirements were met. The retroactive change is why 2020 guidance discussed earlier tax years as well as 2020. It also explains why an old return may reflect procedural choices that cannot be understood from the deduction amount alone.
The allowance was generally automatic unless a class election changed it
Bonus depreciation was generally mandatory for qualified property unless a valid election excluded a class of property. The class-based design matters: the federal election applied to all qualified property in the same class placed in service during that tax year, rather than allowing the taxpayer to select individual assets within the class.
The 2020 IRS guidance also addressed limited procedures for late elections, withdrawals, revocations, amended returns, administrative adjustment requests, and accounting-method changes. Those historical procedures had defined conditions and time limits. Their existence does not mean that the same procedural route remains open in 2026 or applies to every old return.
Bonus depreciation changed timing, basis, and later-year deductions
A full first-year depreciation deduction accelerated cost recovery. Once depreciable basis was recovered through the allowance, that same basis was not available for ordinary depreciation again in later years. That is why comparing only the first-year deduction can give an incomplete picture: the rule affected when depreciation appeared, not merely how the asset was described.
Other federal provisions could interact with the calculation. Section 179 expensing was a separate mechanism with its own limits and ordering rules. Listed property, including some passenger vehicles, could face additional limitations. Business-use changes, dispositions, and recapture rules could matter later. These separate systems are one reason “100% bonus depreciation” was never a complete conclusion about a particular asset.
Federal eligibility did not guarantee matching state treatment
Section 168(k) is a federal income-tax rule. States decide how their own tax laws connect to the Internal Revenue Code, and that connection can be current, fixed to an earlier version of federal law, or modified through state additions and subtractions. A state may therefore decouple from federal bonus depreciation or spread the state deduction differently.
A national description of 2020 bonus depreciation can accurately explain the federal framework, but it cannot establish the treatment on every state return. That question belongs to the law of the relevant state and the version in force for the tax year being examined.
The current 2026 rule is different from a simple continuation of 2020 law
The historical phase-down originally moved from 100% for most qualified property placed in service through 2022 to 80% in 2023, 60% in 2024, 40% in 2025, and 20% in 2026. Later legislation changed that path.
As of August 8, 2026, federal law provides a permanent 100% additional first-year depreciation deduction for qualifying property acquired and placed in service after January 19, 2025. IRS guidance also identifies a transition: qualified property placed in service after December 31, 2024, and before January 20, 2025, generally remained at 40%, with 60% applying to certain longer-production-period property and certain aircraft.
This current 100% rate does not rewrite what happened in 2020. The two periods may share a percentage, but they rest on legislation with different effective-date rules. A historical explanation should use the law governing the 2020 transaction; a current explanation should use the later statute and 2026 guidance.
A 2020 record must be read as a collection of facts
A depreciation schedule may show the result without revealing every premise behind it. Understanding a historical entry can require the asset description, depreciable basis, acquisition documents, placed-in-service evidence, recovery class, business-use information, elections, and any later accounting adjustments.
Those records answer different questions. An invoice may show acquisition cost. Installation or operational records may help establish when property was ready and available for use. Form 4562 and the depreciation schedule show how the federal return treated the asset. None of those documents, standing alone, necessarily proves every requirement of Section 168(k).
The clearest summary is therefore narrow: 2020 bonus depreciation generally offered a 100% federal additional first-year deduction for qualifying property within the applicable dates, but classification, timing, exclusions, elections, and later changes remained essential. The return of a 100% allowance after January 19, 2025, is current context—not a substitute for the historical rule.
Sources
- IRS additional first-year depreciation deduction FAQs
- IRS Internal Revenue Bulletin 2020-19, including Revenue Procedure 2020-25
- IRS Internal Revenue Bulletin 2020-48, including the 2020 final bonus-depreciation regulations
- IRS Publication 946 for 2020, How To Depreciate Property
- Treasury and IRS 2026 release on the amended additional first-year depreciation deduction
- IRS Notice 2026-11 on the permanent 100% additional first-year depreciation deduction
- IRS Topic No. 704, Depreciation
