Tax Planning

Maximizing the Section 45Z Clean Fuel Production Credit in the New OBBB Era

With recent changes under the One, Big, Beautiful Bill, producers of clean transportation fuel face updated eligibility, emissions, and foreign entity requirements—this article breaks down what’s new and how to comply.

By NomadicTax Research Team • 5-8 min read • March 12, 2026

## Background: What’s Section 45Z and Why It Matters Section 45Z offers an income tax credit for domestic producers of clean transportation fuel. Originally enacted under the Inflation Reduction Act (IRA), this credit has been altered by the One, Big, Beautiful Bill (OBBB) to include extended deadlines, tighter eligibility rules, and new compliance requirements. Understanding those changes is essential for producers and intermediaries. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-issue-proposed-regulations-on-the-clean-fuel-production-credit-under-the-one-big-beautiful-bill?utm_source=openai)) ## Key Changes Under OBBB Here are the updated rules as of early 2026: - **Extension of credit window**: Fuel sold through December 31, 2029 now qualifies, extending beyond the former 2027 termination. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-issue-proposed-regulations-on-the-clean-fuel-production-credit-under-the-one-big-beautiful-bill?utm_source=openai)) - **Feedstock restrictions**: Only feedstocks grown/produced in the U.S., Mexico, or Canada qualify for fuel produced after December 31, 2025. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-issue-proposed-regulations-on-the-clean-fuel-production-credit-under-the-one-big-beautiful-bill?utm_source=openai)) - **Emissions rate rules**: Negative emissions rates are generally prohibited (except for fuels derived from animal manure), emissions calculations exclude indirect land-use changes, and SAF (Sustainable Aviation Fuel) loses its special higher rate. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-issue-proposed-regulations-on-the-clean-fuel-production-credit-under-the-one-big-beautiful-bill?utm_source=openai)) - **Prohibited Foreign Entity (PFE) rules**: Specified foreign and foreign-influenced entities may be disqualified from claiming the credit. Interim safe harbors are available; Notice 2026-15 provides guidance. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-provide-guidance-for-certain-energy-tax-credits-regarding-material-assistance-provided-by-prohibited-foreign-entities-under-the-one-big-beautiful-bill?utm_source=openai)) ## Practical Examples - A U.S.-based biodiesel plant using animal-manure feedstock can still get the credit and may qualify for negative emissions; but after 2025, any feedstock from outside the U.S., Canada, or Mexico is disallowed. - A clean fuel producer selling fuel through related entities must ensure that the sale attribution rules under the new regulations apply so the credit is correctly claimed. - A foreign-influenced entity must examine whether it is “specified foreign” or subject to the foreign-influenced test; reliance on safe harbors under Notice 2026-15 might be essential during the transition. ## Actionable Steps to Stay in Compliance and Maximize Benefit 1. **Register early** under IRC § 4101—make sure Form 637 is filed in time so production periods are covered. Missing registration deadlines can nullify credits. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-issue-proposed-regulations-on-the-clean-fuel-production-credit-under-the-one-big-beautiful-bill?utm_source=openai)) 2. **Document feedstock origins** and emissions pathways—the new rules require proof of sourcing from U.S., Mexico, or Canada post-2025. 3. **Compute emissions rates carefully**, ensuring you exclude indirect land-use changes and treat SAF per the new rules. Use interim guidance if applicable. 4. **Use interim safe harbors** under Notice 2026-15 if you face uncertainties around PFE categorization or calculating the Material Assistance Cost Ratio (MACR). Substantiate safe-harbor reliance. ([irs.gov](https://www.irs.gov/newsroom/treasury-irs-provide-guidance-for-certain-energy-tax-credits-regarding-material-assistance-provided-by-prohibited-foreign-entities-under-the-one-big-beautiful-bill?utm_source=openai)) 5. **Watch for final regulations and comment periods**, especially REG-121244-23; your feedback may shape rules on ownership and excise registration. ([assets.ctfassets.net](https://assets.ctfassets.net/t0ydv1wnf2mi/6yQNDsvBZIrK1WAF0wxF0B/1a4a425ef73116b307f32c7ba4ba7a03/Stay_Current_IRS-and-Treasury-Release-Proposed-Regulations-on-the-Section-45Z-Clean-Fuel-Production-Credit.pdf?utm_source=openai)) ## Conclusion For clean fuel producers, the OBBB updates to Section 45Z are transformative. To benefit, you must not just understand the new rules—but actively adapt: align feedstock sourcing, emissions reporting, registration timing, and entity classification. Doing so can unlock full credit benefits before the 2029 cutoff and avoid costly compliance pitfalls. **Category:** Tax Planning **TaxHome:** US **Author:** NomadicTax Research Team **ReadTime:** 5-8 min **Published:** true