New 2025 Prescription Drug Event (PDE) File Layouts (FINAL)

Beginning January 1, 2025, new PDE file layouts will become effective, and Part D sponsors must use the new 2025 PDE Inbound File Layout to submit PDE records for all Benefit Years and all Dates of Service (DOS), including Benefit Years prior to 2025 and DOS prior to January 1, 2025. PDE response files sent from CMS to Part D sponsors will also follow the new 2025 PDE Outbound File Layout, beginning January 1, 2025. Additional information regarding the new PDE file layouts can be found in the April 18, 2023, HPMS memo, Subject: New 2025 Prescription Drug Event (PDE) File Layouts (FINAL). The existing PDE Inbound File Layout, published on the CSSC Operations website under File and Report Layouts, will be accepted prior to the effective date of the 2025 PDE Inbound File Layouts on January 1, 2025.


In the event you have questions, please contact CSSC Operations at 1-877-534-2772 (option 2) or by email at

Last Updated: 05/02/2023