The first wave of 45z tax credit transactions in 2025 looked pretty much like every other credit type in the transferable market. Single buyer, single seller, lump-sum payment, one-shot closing. The structure was borrowed wholesale from the solar and wind ITC playbook because that’s what the market knew.
That template is already breaking apart. Club deals, quarterly payment schedules, carryback-aligned timing, and multi-year strips are replacing the single-closing model that defined the market’s first year.
For corporate buyers and fuel producers entering the 45Z tax credit market in 2026, understanding these structural shifts isn’t optional.
The Club Deal Has Arrived
In Q1 2026, Reunion Infra facilitated a $30 million §45Z transaction between a major Midwest ethanol producer and two publicly traded banks. The deal was structured as a “club,” with both buyers sharing legal counsel, a single accounting firm for diligence, and coordinated commercial terms.
Running two independent transactions would have doubled the diligence burden and slowed the timeline. The club model let both banks underwrite against the same diligence package while negotiating individualized purchase agreements. The seller faced one set of questions instead of two. Tax credit insurance was structured with a limit of liability of at least 125% of transaction volume.
This is a deal structure that didn’t exist in the 45z tax credit market a year ago. Expect it to become standard for larger transactions.
Quarterly Payments Are Replacing Lump Sums
Here’s the structural shift that matters most for cash flow planning.
The Reunion club deal used quarterly fundings across 2026 and into 2027 rather than a lump-sum payment. That’s a significant departure from the one-and-done model that dominated early 45z tax credit transactions.
Quarterly structures make sense for production credits because the credits themselves are generated over time as fuel is produced and sold. Quarterly fundings align cash disbursement with credit production, reducing timing mismatch risk. For corporate treasury teams, that means the purchase can be modeled alongside estimated tax payment schedules rather than treated as a single large outflow.
Sellers benefit too. Predictable working capital across the production period beats a single payment that might require bridge financing.
Strips and Multi-Year Commitments Are Emerging
The strip structure, already established in the PTC market (where nearly $9 billion in long-term strips were purchased in 2025 according to Crux), is starting to show up in §45Z.
A strip is a multi-year forward commitment where the buyer agrees to purchase a defined volume of future credits from the same producer across multiple tax years. The OBBBA’s extension of the credit through 2029 is what made multi-year 45z tax credit strips viable. A four-year runway gives both sides enough duration to justify the structuring work.
According to Mickelson & Company, multi-year transactions are already being used to lock in predictable tax offsets and smooth effective tax rates across fiscal years. Producers with stable output and consistent CI scores can now offer something closer to a programmatic tax credit supply rather than a one-off transaction.
Carryback Structures Are Shaping Deal Timing
Nearly half of all tax credits purchased in 2025 were allocated to tax years other than the credit year, according to Crux. That includes significant carryback-driven volume where buyers purchased current-year credits and applied them to prior-year liability.
Reunion Infra reported supporting a publicly traded buyer who purchased 2025 §45 PTCs for a carryback with delayed payment into June 2026. That timing flexibility, where payment is deferred until the buyer’s refund cycle is underway, is now being adapted for 45z tax credit deals.
For sellers, accommodating delayed payment means carrying working capital longer. For buyers, it means cash outflow aligns with the IRS refund timeline rather than front-loading at closing.
Conclusion
The 45z tax credit market has outgrown the structure it was born into. The single-buyer, lump-sum model that worked in 2025 is giving way to club deals, quarterly payment schedules, multi-year strips, and carryback-aligned timing.
For corporate buyers, that evolution means more flexibility to match credit purchases to your actual tax position and cash flow cycle. For fuel producers selling credits through a clean energy tax credit marketplace, it means building the operational infrastructure to support more complex deal structures, because that’s where the market is heading.
The participants who adapt are capturing the best pricing and the most reliable buyer relationships. The ones still running 2025’s playbook are going to find the market has moved on without them.
