On July 4, 2025, the One Big Beautiful Bill Act (OBBBA) was signed into law, bringing significant federal tax changes for businesses and individuals. As the one-year anniversary approaches, several provisions now have near-term deadlines that may affect 2025 tax return preparation, amended return filings, project timelines, and credit eligibility.
Some dates create planning opportunities. Others are cutoff dates for credits and deductions that are being phased out sooner than originally expected, particularly in the clean energy area.
Businesses, real estate owners, developers, energy project sponsors, dealerships, fleet owners, and individuals with qualifying investments should review these dates now. In several cases, waiting until year-end may be too late.
Key OBBBA Dates to Watch
- September 30, 2025 — Clean vehicle credits ended.
The previously owned clean vehicle credit, new clean vehicle credit, and qualified commercial clean vehicle credit generally are not available for vehicles acquired after September 30, 2025. For these credits, a vehicle is generally treated as acquired when there is a written binding contract and a payment, including a nominal down payment or trade-in. The vehicle still must be placed in service to claim the credit. This remains relevant for 2025 tax return preparation. - December 31, 2025 — Individual home energy credits ended.
The energy efficient home improvement credit generally does not apply to property placed in service after December 31, 2025. The residential clean energy credit generally does not apply to expenditures made after December 31, 2025. For residential clean energy property, installation timing is especially important because an expenditure is generally treated as made when original installation is completed. - June 30, 2026 — Alternative fuel vehicle refueling property credit ends.
The Section 30C credit generally is not available for property placed in service after June 30, 2026. Businesses, real estate owners, developers, municipalities, tax-exempt organizations, and individuals with electric vehicle charging or other qualifying refueling projects should confirm whether the property can be fully installed, operational, and placed in service by that date. - June 30, 2026 — Energy efficient commercial buildings deduction cutoff.
The Section 179D deduction generally is not available for property whose construction begins after June 30, 2026. Building owners, designers, engineers, architects, contractors, and tax-exempt building stakeholders should review project timelines, construction-start documentation, energy modeling, and allocation requirements. - June 30, 2026 — New energy efficient home credit cutoff.
The Section 45L credit generally is not available for qualified new energy efficient homes acquired after June 30, 2026. Homebuilders and developers should review closing schedules, certification timing, and project pipelines. - Before July 5, 2026 — Wind and solar construction deadline.
Applicable wind and solar facilities generally must begin construction before July 5, 2026, to avoid the accelerated December 31, 2027, placed-in-service termination rule for the clean electricity production credit and clean electricity investment credit. - July 6, 2026 — Small business retroactive R&E election deadline.
Certain eligible small businesses may elect to apply the new federal domestic research and experimentation, or R&E, expensing rules retroactively to taxable years beginning after December 31, 2021. The statutory one-year deadline falls on July 4, 2026, but because that date falls on a Saturday, the deadline moves to Monday, July 6, 2026. Taxpayers should model state conformity separately. For example, New York’s recently enacted budget legislation decouples from federal immediate expensing for R&E expenditures for taxable years beginning on or after January 1, 2025, generally requiring foreign and domestic R&E expenditures to be amortized over a 60-month period for New York purposes. - July 6, 2026 — Related Section 280C election or revocation deadline.
Eligible small businesses making the retroactive R&E election may also need to make or revoke a Section 280C(c)(2) reduced-credit election for affected prior years by July 6, 2026. Taxpayers that claimed, or could have claimed, the federal research credit should model the R&E deduction and credit impact together before filing amended returns. - December 31, 2027 — Wind and solar placed-in-service deadline.
For applicable wind and solar facilities that are subject to the accelerated termination rule, the Section 45Y clean electricity production credit and Section 48E clean electricity investment credit generally are not available if the facility, or qualified property that is part of the facility, is placed in service after December 31, 2027. - December 31, 2027 — Clean hydrogen construction deadline.
The clean hydrogen rules were also accelerated, with the relevant cutoff generally tied to clean hydrogen facilities that begin construction after December 31, 2027. Although this deadline is less immediate, hydrogen projects often have long development timelines and should be reviewed early.
How Does the IRS Determine When Construction Has Begun?
In situations where construction needs to begin prior to a specific date in order to maintain eligibility for the tax credits, the IRS employs a “Physical Work Test” that outlines the minimum criteria that must be met to determine if physical work of a significant nature has started. Merely engaging in preliminary activities, such as designing, surveys, clearing of land, etc., will not be sufficient to meet this standard.
Alternatively, the IRS also allows for a “Five Percent Safe Harbor” stating that, in general, construction is considered to have begun if the taxpayer pays or incurs at least five percent of the total cost of the facility, and thereafter makes continuous efforts to advance towards the project’s completion. However, taxpayers should be aware that the Five Percent Safe Harbor is no longer available for wind and most solar projects.
In any event, it is critical to have a written, binding agreement in place before the applicable dates noted above.
The July 6 R&E Deadline Deserves Special Attention
One of the most taxpayer-favorable business changes in the OBBBA was the restoration of immediate expensing for domestic R&E costs, including domestic software development costs, for taxable years beginning after December 31, 2024. Taxpayers may instead elect to capitalize and amortize those costs over at least 60 months.
For certain small businesses, the law also created a retroactive election. Eligible taxpayers may elect to apply the new domestic R&E rules to taxable years beginning after December 31, 2021, allowing qualifying businesses to revisit years affected by the prior capitalization rules.
An eligible taxpayer generally is a taxpayer that is not a prohibited tax shelter and that meets the Section 448(c) gross receipts test for the first taxable year beginning after December 31, 2024. For a taxable year beginning in 2025, the inflation-adjusted gross receipts threshold is $31,000,000.
The election generally requires the filing of amended returns or, for certain partnerships, administrative adjustment requests for each of the impacted years. These filings must be made by July 6, 2026.
State tax treatment should be reviewed separately. New York, for example, has decoupled from the federal R&E changes for taxable years beginning on or after January 1, 2025. As a result, a taxpayer that deducts domestic R&E expenditures currently for federal purposes may be required to add back the federal deduction and compute a separate New York amortization deduction over 60 months. This can create different federal, New York State, and, where applicable, local tax results.
There is one important trap: the OBBBA did not extend the normal refund claim statute. A refund claim generally must be filed by the later of three years from the time the return was filed or two years from the time the tax was paid, and the refund amount may be limited by the normal lookback rules.
That means July 6, 2026, is not always the only date that matters. A taxpayer reviewing a 2022 year should confirm the original filing date, any extension, payment dates, and the applicable refund claim deadline before assuming a refund is still available.
Do Not Review R&E Without Reviewing the Research Credit
The retroactive R&E election should be considered together with the federal research credit.
The OBBBA transition rules allow an eligible taxpayer making the retroactive R&E election to make or revoke a Section 280C(c)(2) election on an amended return. IRS guidance confirms that late Section 280C(c)(2) elections and revocations for eligible prior years must be filed on or before July 6, 2026.
This matters because Section 280C affects the relationship between the research credit and the deduction for research expenses. A taxpayer changing prior-year R&E treatment should review the credit calculation, reduced-credit election, taxable income, state tax effects, net operating losses, and credit carryforwards before filing amended returns.
Energy Credits: Timing & Documentation Matter
The OBBBA accelerated the expiration of several clean energy incentives enacted or expanded under the Inflation Reduction Act. Some deadlines have already passed, but they still matter for 2025 returns. Others are quickly approaching.
For clean vehicle credits, taxpayers should review contracts, payment records, vehicle identification numbers, time-of-sale reports, dealer documentation, credit transfer records, and placed-in-service dates.
For home energy credits, taxpayers should keep copies of invoices, proof of installation, product eligibility records, manufacturer certifications, and any required identification information. For residential clean energy property, the installation completion date may be more important than the payment date.
For Section 30C, Section 179D, Section 45L, wind, solar, and hydrogen projects, taxpayers should map project timelines against the relevant placed-in-service, acquisition, or construction-start deadlines. Ordering equipment, signing contracts, or beginning preliminary work will likely not be enough.
Federal credit expirations do not necessarily end the analysis. State and local credits, grants, rebates, exemptions, utility incentives, and other economic development programs may still be available even where a federal credit has expired or is being phased out. Those programs are outside the scope of this article, but taxpayers should consider them when evaluating project economics.
What Businesses & Individuals Should Do Now
Taxpayers should take the following steps before the applicable deadlines:
- Review 2022–2024 R&E costs. Eligible small businesses should model whether the retroactive R&E election produces refunds, reduces future amortization, changes credits, or affects state tax filings.
- Check refund claim deadlines. For 2022 years in particular, the normal refund statute may expire before July 6, 2026, depending on filing and payment history.
- Coordinate R&E deductions with research credits. The Section 280C election or revocation decision should be analyzed before amended returns or administrative adjustment requests are filed.
- Review state conformity. Federal R&E expensing, the retroactive small business election, Section 280C elections, and refund claims may not produce the same result for state income tax purposes. Taxpayers with New York filing obligations should separately model the New York addback and 60-month amortization rules for R&E expenditures.
- Take an inventory of energy projects currently in process. Projects involving electric vehicle charging, commercial building energy improvements, new energy efficient homes, wind, solar, or hydrogen should be matched to the applicable deadline.
- Document timing carefully. Eligibility may turn on when a vehicle was acquired, when property was placed in service, when installation was completed, when a home was acquired, or when construction began.
- Review 2025 tax returns for expired credits. Clean vehicle and home energy credits may still be available on 2025 tax returns if the timing rules and other eligibility requirements were met before the applicable cutoff.
- Consider state and local incentives. Even where a federal clean energy credit has expired, taxpayers should determine whether state or local credits, rebates, grants, property tax incentives, sales tax exemptions, or utility programs remain available.
- Update transaction documents. Purchase agreements, construction contracts, tax credit transfer agreements, and financing documents should address the impact of missed credit deadlines.
The OBBBA is moving from enactment to implementation. For many taxpayers, the best tax result will depend on acting before a specific date passes.
The One Big Beautiful Bill Act: One Year Later
Want to stay ahead of the latest developments under the One Big Beautiful Bill Act? Join our upcoming webinar on Tuesday, June 23, from 10:30 – 11:30 AM, where our tax professionals will break down key post-enactment IRS and Treasury guidance. Gain practical insights into effective dates, transition rules, documentation requirements, planning opportunities, and unresolved issues that could impact your business. Register and learn more here.
This material has been prepared for general, informational purposes only and is not intended to provide, and should not be relied on for tax, legal or accounting advice. Should you require any such advice, please contact us directly. The information contained herein does not create, and your review or use of the information does not constitute, an accountant-client relationship.
