Medicare Prescription Drug Program
(Part D)

Last updated October 2023

Part D is a voluntary prescription drug insurance program through Medicare called “Medicare Prescription Drug Coverage” that started January 1, 2006. Medicare created a standard benefit design and has private insurance companies’ market plans that are equal to or better than the standard benefit design. Click here to see the 2024 adjusted standard benefit design (benchmark).

This drug coverage is available to everyone who has Medicare, regardless of income or health status. In California, there are 23 Part D drug plans to choose from in 2024. Plans range in price from around $0.40 to $188 per month. If you have a limited income, you may receive “extra help” to cover prescription drugs for little or no cost. To find out if you are eligible for extra help, call Social Security at 1-800-772-1213.

Higher income seniors may be charged an “adjustment” amount if they enroll in a Part D drug plan. The amount is based upon the extent modified adjusted gross income exceeds $103,000 ($206,000 for married couples). This is called the Income Related Monthly Adjustment Amount or IRMAA. Please click here for the complete 2024 IRMAA income chart.

In addition to a monthly premium, you will also have a share of costs determined by the plan you select. Companies have some flexibility with the drugs they choose to cover under their plan (called a drug formulary) and the pharmacies they contract with, but there are some minimum standards that are strictly enforced. Plans run for a calendar year at which point they can be renewed for another calendar year or replaced with another plan during Annual Enrollment Period (AEP). The AEP begins on October 15 and runs through December 7 of each year. Though this is a voluntary program, you may be penalized if you do not enroll when you are first eligible but enroll at a later time, and you haven’t carried equivalent coverage from another source.

OnlyHealthInsurance does not represent, sell or market Medicare Part D drug plans, but has found the best way we can be of service is as an objective advisor. We provide a one-time complimentary Medicare Part D plan recommendation for our new Medicare Supplement clients. If you’re not a Medicare Supplement client of ours but still would like our help, we provide this service for a fee. Please read our annual letter that explains how we can help you and what we charge.

To review plans on your own, visit Medicare’s web site at Medicare’s Part D Drug Plan Finder allows you to enter your personal prescription drug information and other preferences, evaluate plans and enroll online.

Note: It is very important to discuss your particular circumstances with an insurance professional. By enrolling in a Prescription Drug Plan, you may “void” your current medical insurance. If you are unsure about your eligibility contact Medicare or Social Security.

                       Give us a call today at 1-800-924-1411 and we’ll send you our complimentary Part D Facts Kit.

📞 Important Medicare Phone Numbers


  • For Medicare Enrollment: Contact the Social Security Administration (SSA) at 1-800-772-1213
  • For Medicare Part A and Part B Coverage Questions: Call 1-800-MEDICARE (1-800-633-4227)
  • For government sponsored assistance with Medicare and Social Security contact HICAP (Health Insurance Counseling and Advocacy Program) at 1-800-434-0222