Nationwide Audit of Medicare Part D Eligibility Verification Transactions

An E1 transaction is a Medicare Part D eligibility verification transaction that the pharmacy submits to the Part D transaction facilitator to bill for a prescription or determine drug coverage billing order. The Part D transaction facilitator returns information to the pharmacy that is needed to submit the prescription drug event. E1 transactions are part of the real-time process of the Coordination of Benefits and calculating the true out-of-pocket costs (CMS, Medicare Prescription Drug Benefit Manual, Pub. No. 100-18, chapter 14, § 30.4). We will review CMS's oversight of E1 transactions processed by contractors and determine whether the E1 transactions were created and used for intended purposes.

Announced or Revised	Agency	Title	Component	Report Number(s)	Expected Issue Date (FY)
Revised	Centers for Medicare & Medicaid Services	Nationwide Audit of Medicare Part D Eligibility Verification Transactions	Office of Audit Services	W-00-20-35751	2025