2026 CMS Final Rule: Expanded ASP Reporting and Verification Requirements for Manufacturers

On November 5, 2025, CMS released the Calendar Year 2026 Payment Policies Under the Physician Fee Schedule and Other Changes to Part B Payment and Coverage Policies; Medicare Shared Savings Program Requirements; and Medicare Prescription Drug Inflation Rebate Program (“2026 Final Rule”). The regulations take effect January 1, 2026, with expanded manufacturer reporting obligations beginning April 30, 2026.

For pharmaceutical manufacturers, the Final Rule represents a meaningful procedural shift. While CMS stopped short of redefining Fair Market Value (FMV) or Bona Fide Service Fees (BFSFs), it introduced new requirements that significantly expand the scope of documentation and verification expected under the Average Sales Price (ASP) framework.

Manufacturers will now be responsible for submitting all reasonable assumptions supporting ASP calculations, documenting the methodology used to determine FMV, and obtaining certifications from each service fee recipient that those fees are not passed on to downstream entities. These updates introduce a considerable new compliance lift for manufacturers – one that underscores the importance of practical guidance, structured documentation, and proactive coordination across internal teams.

A) Drugs and Biological Products Paid Under Medicare Part B

1. Average Sales Price (ASP): Price Concessions and Bona Fide Service Fees (BFSFs)

CMS has finalized new reporting and verification obligations while declining to adopt a revised definition of BFSFs or formal FMV standards. Key updates include:

• Mandatory ASP Assumption Submission: Manufacturers must now submit all reasonable assumptions used in ASP calculations, including documentation of FMV methodologies for all current, new, and renewed BFSF contracts.
• Verification from Fee Recipients: Each BFSF recipient must provide written certification that the fee is not passed on, in whole or in part, to any downstream entity (e.g., pharmacies or providers), whether or not the entity takes title to the drug for new contracts effective January 1, 2026 or later.
• Bundled Arrangements Clarified: CMS finalized a definition of “bundled arrangements” and guidance on accounting for bundled price concessions in ASP calculations.

Although CMS deferred broader definitional changes, these new documentation and attestation requirements mark a major procedural shift. What had previously been optional now becomes a mandatory component of ASP submissions, with greater scrutiny expected in CMS reviews.

2. Average Sales Price: Units Sold at Maximum Fair Price (MFP)

CMS clarified that units sold at the Maximum Fair Price will now be included in ASP calculations beginning January 1, 2026. The Part B Drug Payment Limit File will display MFP-based payment limits for applicable products.

3. Cell and Gene Therapy Payments

CMS will continue its bundled payment approach for CAR T-cell and autologous gene therapies. It did not finalize its earlier proposal to exclude manufacturer-paid preparatory services from BFSF treatment. Those services may still qualify as BFSFs if they meet the existing Four-Part Test under 42 CFR §414.802.

4. Discarded Drug Refunds

CMS reviewed two requests to adjust refund percentages under the Part B discarded drug refund program but finalized no changes for CY 2026.

B) Medicare Prescription Drug Inflation Rebate Program

Under the Inflation Reduction Act (IRA), CMS finalized several new policies for both the Part B and Part D Inflation Rebate Programs, effective January 1, 2026:

• Claims-Based 340B Exclusion: CMS will implement a claims-based methodology to remove 340B units from Part D rebate calculations, reducing double-counting risk.
• 340B Data Repository: CMS is establishing a voluntary 340B claims data repository to allow covered entities to submit claims data for testing and validation.
• Program Alignment: These changes align the rebate structure more closely across Parts B and D, signaling CMS’s intent to strengthen consistency and transparency in inflation rebate reporting.

For manufacturers, these provisions will require enhanced coordination between government pricing, rebate, and 340B data teams, as well as systems capable of isolating 340B transactions under CMS’s new claims-based methodology.

Next Steps for Manufacturers

• Begin compiling all ASP assumptions and FMV documentation for each BFSF well ahead of the April 30, 2026 submission deadline.
• Implement processes to obtain and retain verification letters from all service fee recipients.
• Update ASP and rebate systems to track MFP sales and 340B claims under CMS’s revised methodologies.
• Treat all BFSF documentation as part of formal CMS audit readiness procedures.

Looking Ahead

The 2026 Final Rule establishes new expectations for documentation and third-party verification under ASP reporting. Manufacturers will now need to submit all reasonable assumptions, provide FMV documentation for service fees, and secure certification letters from each recipient confirming that fees are not passed on.

These changes represent a significant operational shift that will require careful coordination across pricing, contracting, and compliance functions.

At Prescription Analytics, we recognize the scope of this transition and are here to help manufacturers prepare with confidence. We provide expert, hands-on support for Government Pricing, Rebate Processing, Chargeback Processing, State Price Transparency Reporting, and other processing and compliance services to help clients strengthen compliance frameworks, refine SOPs, enhance ASP reporting, and adapt effectively to evolving regulatory requirements.