How Big Is the Transferable Tax Credit Buyer Market, and How Fast Is It Growing?

The first of five data-driven posts exploring how companies are participating in the transferable tax credit market.

Section 6418 of the Inflation Reduction Act created a new market for companies to purchase clean energy tax credits – a mechanism that previously didn't exist in U.S. tax code. Two years in, we took a look at the buyer universe to understand its size and composition.

How Many Companies Have Publicly Disclosed Transferable Tax Credit Purchases?

As of early March 2026, 119 public companies – approximately 8.4% of the ~1,400 largest U.S. public companies – have disclosed purchasing transferable tax credits in SEC filings.

Reunion analyzed over 6,000 public filings across approximately 1,400 of the largest U.S. public companies to quantify buyer participation. ASU 2023-09, a new accounting standard in effect for fiscal years beginning after December 15, 2024, requires more granular tax disclosures by public companies and makes credit purchases easier to verify. 

The above count reflects human-verified disclosures in 10-K, 10-Q, 20-F, and 40-F filings filed since January 1, 2025. The 119 verified purchasers span 30+ states and 11 industry sectors. They range from Fortune 100 corporations to regional banks.

How Fast Is the Transferable Tax Credit Market Growing?

Across the nearly 1,000 public companies in our dataset that filed annual disclosures in both 2024 and 2025, we found that the share of firms disclosing tax credit purchases rose from 4.9% in 2024 to 8.5% in 2025 – an increase of approximately 74%.

Growth was broad-based across sectors and company sizes, though it was particularly pronounced among smaller taxpayers. Companies with under $200M in annual tax expense doubled their purchase rate. Participation is broadening thanks to more standardized deal structures, increases in credit supply, and clarified IRS guidance.

Why This Matters

The transferability provision of the IRA fundamentally expanded the buyer community beyond the small group of traditional tax-equity investors that historically participated in clean energy finance. Any corporation with federal tax liability can now purchase credits directly, and the filing data shows they are doing so in increasing numbers. The 119 verified purchasers represent only publicly disclosed transactions. The actual buyer count, including private companies and transactions below disclosure thresholds, is almost certainly larger.

For the next post that explores tax credit purchase rates by company size and effective tax rates, [click here.]

Reunion maintains a database of public companies that have disclosed transferable tax credit purchases, available to entities buying or selling credits, and provides exclusive access to the underlying SEC data to existing buy-side and sell-side clients of Reunion. Reach out to your Reunion contact for access.

Data Notes

Analysis Period: February-March 2026

Universe: ~1,400 largest U.S. public companies

Filings Reviewed: 10-K, 10-Q, 20-F, 40-F filed since January 1, 2025

Methodology:

• Credit Classification: Many filings reference transferable credits without specifying type. These are classified as clean energy credits since transferability is generally tied to Section 6418.
• Sample Composition: Of approximately 1,400 companies, roughly 1,000 had filed both 2024 and 2025 reports during the analysis window. The remainder had not yet filed 2025 reports or had 2024 filings published before data collection began.
• Data Quality: An AI-assisted process was used to scan filings. All identified purchasing activity was then human-verified at the company level.