NCSL Tools for State Legislatures:
Medicare Prescription Drug Coverage

  NCSL Rx Resources |  CMS/HHS Resources  


Updated: June 2018

Medicare Part D in 2016-2018 and Trends over Time

For early 2018, nearly 44 million of the 57 million people on Medicare were enrolled in a prescription drug Part D plan.

States do not regulate or control these federally established insurance-style plans, but they affect state health policy in 2-3 ways. These include 1) More than a dozen states have prescription drug assistance programs (SPAPs) that "wrap-around" or add to the Part D benefits, especially drugs bought by Medicare patients during the so-called "donut hole" spending category; 2) drugs covered under Medicare Part D can mean that state Medicaid programs do not have pay or reimburse drug costs for certain dual-eligible enrollees; 3) The ACA requires certain preventive services to be broadly available and covered, for much of the U.S. population, including Medicare.

A new chart based report by Kaiser Family Foundation examines Medicare Part D prescription drug coverage enrollment, premiums, benefit design, cost sharing, and other marketplace features in 2016 and changes over time. The report includes data on enrollment by firm, state-level estimates of enrollment and premiums, and information about Part D enrollees who are receiving extra help through the Part D Low-Income Subsidy (LIS) program that helps reduce premiums and cost sharing. Among the key findings:

  • Most Part D enrollees (60 percent) are in stand-alone prescription drug plans (PDPs), but a rising share (40 percent in 2016, up from 28 percent in 2006) are in Medicare Advantage prescription drug (MA-PD) plans.
  • Three firms—UnitedHealth, Humana, and CVS Health—account for over half (53 percent) of all Part D enrollment in 2016.
  • Of the 12 million Part D enrollees who receive the LIS, 1.5 million beneficiaries pay a monthly premium for Part D coverage, even though premium-free PDPs are available in all regions.  (Report released online 9/2016)
  • What's Medicare Supplement Insurance (Medigap)?    A Medicare Supplement Insurance (Medigap) policy, sold by private companies, can help pay some of the health care costs that Original Medicare doesn't cover, like copayments, coinsurance, and deductibles.
  • Medigap Enrollment and Consumer Protections Vary Across States 
     In all but four states insurance companies can deny private Medigap insurance policies to seniors after their initial enrollment in Medicare because of a pre-existing medical condition, such as diabetes or heart disease, except In ,under limited, qualifying circumstances, a KFF analysis finds. One in four people in traditional Medicare had a Medigap policy in 2015  (News ReleaseIssue Brief)






Read the ReportFor 2017-2018 and future years coverage, the open enrollment period (AEP) is once a year, from October 15 to December 7.  Medicaid plus Medicare "Dual eligible" enrollees and persons newly eligible for Medicare (turning age 65, etc.) may sign up throughout the year. Beginning each fall, Medicare’s 50 million beneficiaries have an opportunity to sign up for new coverage under a Medicare Advantage plan or a Medicare stand-alone Part D drug plan, or change plans if they are already enrolled in either type of plan.

Medicare Advantage, Cost, PACE, Prescription Drug Plan - Summary Report (Data as of February 2018)

Current Contract Summary:

Advantage (MA) Only Enrollees

Drug Plan Enrollees

SNP Enrollees

Employer Plan Enrollees (800 Series Plans)

Total Enrollees

Total "Prepaid" Contracts






  MA Subtotal






  Other Subtotal






Total PDPs



















For comparison, as of Dec. 15, 2015 CMS reported: 

  • Total enrollment in Medicare Advantage and other prepaid plans increased by 36,254 to 17,761,121 as of the Dec. 1 payment date. Local MA coordinated care plan membership increased by 37,860 to total 15,210,201, while private fee-for-service dropped by 873 to reach 252,673.
  • Enrollment in MA Special Needs Plans rose by 16,619 to 2,150,380, and Medicare-Medicaid dual-eligible plans fell by 7,273 lives to total 371,367. Visit CMS Enrollment Summaries, updated monthly. [URL reviewed 9/2016]
  • Closing the prescription drug “donut hole” The Affordable Care Act makes Medicare prescription drug coverage more affordable by gradually closing the gap in coverage where beneficiaries had to pay the full cost of their prescriptions out of pocket, before catastrophic coverage for prescriptions took effect. The gap is known as the donut hole. The donut hole will be closed by 2020.   Because of the health care law, in 2011, beneficiaries in the donut hole began receiving discounts and savings on covered brand-name and generic drugs. People with Medicare Part D who are in the donut hole in 2016 receive discounts and savings of 55 percent on the cost of brand name drugs and 42 percent on the cost of generic drugs. For state-by-state information on discounts in the donut hole, go to: Part D dount hole savings by state YTD 2015.

  • For more information about Medicare prescription drug benefits, go to:

  • Medicare preventive services The Affordable Care Act added coverage of an annual wellness visit and eliminated coinsurance and the Part B deductible for certain recommended preventive services covered by Medicare, including many cancer screenings and other important benefits. By making certain preventive services available with no cost sharing, the Affordable Care Act removes barriers to prevention, helping Americans take charge of their own health and helping individuals and their providers better prevent illness, detect problems early when treatment works best, and monitor health conditions. For state-by-state information on utilization of an annual wellness visit and preventive services at no cost to Medicare beneficiaries, please visit:

This web page provides helpful and updated materials.  Some of the material is designed so it can be printed or downloaded for use in a legislative district. 



Beginning in 2005 NCSL worked with the Centers for Medicare and Medicaid Services (CMS) to provide timely, user-friendly materials to state legislators so they may inform their constituents, colleagues, friends, family members and loved ones about the opportunities and requirements for the new benefit. (1)

 CMS State Resources Web Page          ncsl domeCMS Identity Mark

  • Rx Sessions at NCSL Fall Forum in San Antonio, Texas - December 2006.   
    Update on State Actions Related to Medicare Part D Prescription Drug Coverage
    On January 1, 2007, the second year of Medicare pharmaceutical benefits began.  Many states continue to play a significant role for seniors and persons with disabilities needing medicines - by providing "wrap around" subsidies for premiums and coverage gaps, by problem-solving and by sponsoring programs for those not eligible for Medicare.  New commercial plan designs, questions about state "clawback" payments, Medicaid program responses and possible actions in Congress all loom as legislators prepare to tackle state pharmaceutical budgets and policy.  Four experts share news and trends.

    • Steven McAdoo, Deputy Regional Administrator, Centers for Medicare and Medicaid Services (CMS Region 6), Dallas, Texas | PowerPoint [3.8 Mb]

    • Richard Cauchi, Health Program Director, NCSL Staff, Colorado  | PowerPoint

    • Joy Johnson Wilson, Health Policy Director, NCSL staff, Washington, DC

  • "Medicare Prescription Drug Coverage and the States" - Even with the Medicare Part D Program well underway, states continue to play important roles in prescription drug coverage for millions of low-income people.  In addition to supplementing the new federal coverage, many states are modifying their State Pharmaceutical Assistance Programs and making adjustments to Medicaid and other Rx programs.   

    • "Prescription Drug Discounts: from 340B to Consumer Cards." 
      Harry Hagel, Senior Director, HRSA Pharmacy Services Support Center, Washington, DC  PowerPoint OnlineAdobe PDF

    •   * Assemblymember Richard Gottfried, Chair, Assembly Health Committee, New York State

        * Gloria Parker, Associate Regional Administrator, Centers for Medicare and Medicaid Services, Region Four, Atlanta, Georgia  PowerPoint OnlineAdobe PDF
        * Edward Belkin, VP for Communications and Public Affairs, Pharmaceutical Research and Manufacturers of America, D.C.  PowerPoint OnlineAdobe PDF  
        * Moderator: Senator Judy Lee, North Dakota

  • Annual Meeting Rx Sessions  - held August 16, 2006 in Nashville, TN.

  • Medicare Part D: State Updates.  NCSL SPRING FORUM- RX Session:  held Friday, April 7, 2006 in Washington DC. As part of their ongoing efforts to help Medicare.  Speakers:
    * Joseph Fine and Cora Tracy, [PowerPoint download Adobe PDF / slides] - Centers for Medicare and Medicaid Services, Baltimore, MD.
    * Richard Cauchi and Donna Folkemer, [PowerPoint download Adobe PDF / slides] -NCSL staff Directors, Denver and Washington, DC.


(1) The web page was initiated as a partnership between NCSL and CMS in 2005.  The 2008-2016 editions were produced and edited by NCSL, which is entirely responsible for editorial content.

(2) Beginning in 2006, CMS allowed group PFFS plans to submit one national plan application that covers retirees throughout the entire country, instead of submitting multiple applications that target specific counties where retirees live. This applies to non-network PFFS plans only. States may still require plans to be licensed even though CMS does not. "2006 Employer/Union-Only Non-Network Private Fee-For-Service (PFFS) Plan Service Area Waiver Guidance."

Featured Links


"States have very little regulatory authority [under Medicare], and we're concerned we can't hold Medicare Advantage plans responsible for their [sales] agents' actions. That ties our hands behind our backs."

— Guenther Ruch, administrator of Wisconsin's Department of Insurance', speaking at AHIP's Medicare conference