THE ANNUAL ENROLLMENT PERIOD FOR MEDICARE PART D WILL BE: OCTOBER 15TH TO DECEMBER 7th Don't wait until the enrollment period is here to start planning for next year! Get ahead of the crowd by downloading and completing the Medicare Part D Open Enrollment Worksheet today. Alternatively, you can call The Resource Center at 406-259-5212 and request to be put on the Medicare Part D Worksheet mailing list. The worksheets will be mailed out on 9/22/2026. After that date, worksheet