“In 2023, Medicare covered 66.7 million people: 59.1 million aged 65 and older, and 7.6 million disabled. About 48 percent of these beneficiaries have chosen to enroll in Part C private health plans that contract with Medicare to provide Part A and Part B health services. Total expenditures in 2023 were $1,037.0 billion, and total income was $1,024.6 billion, which consisted of $1,014.6 billion in non-interest income and $10.0 billion in interest earnings. Assets held in special issue U.S. Treasury securities decreased by $12.4 billion to $396.7 billion, consistent with the estimate in last year’s report.”
Source: The Boards of Trustees, Federal Hospital Insurance and Federal Supplementary Medical Insurance Trust Funds, 2024 Annual Report of the Boards of Trustees of the Federal Hospital Insurance and Federal Supplemental Medical Insurance Trust Funds, June 6, 2024.
“Together, Parts A and B of Medicare comprise original Medicare, which covers benefits on a fee-for-service basis. Beneficiaries have another option for coverage through private plans, called the Medicare Advantage (MA or Part C) program. When beneficiaries first become eligible for Medicare, they may choose either original Medicare or they may enroll in a private MA plan. Each fall, there is an annual open enrollment period during which time Medicare beneficiaries may choose a different MA plan, or leave or join the MA program.27 Beneficiaries are to receive information about their options to help them make informed decisions.28 In 2020, the annual open enrollment period runs from October 15 to December 7 for plan choices starting the following January. Since 2012, MA plans with a 5-star quality rating have been allowed to enroll Medicare beneficiaries who are either in traditional Medicare or in an MA plan with a lower quality rating at any time.
“Finally, each individual enrolled in either Part A or Part B is also entitled to obtain qualified prescription drug coverage through enrollment in a Part D prescription drug plan. Similar to Part B, enrollment in Part D is voluntary and the beneficiary pays a monthly premium. Since 2011, some higher-income enrollees pay higher premiums, similar to enrollees in Part B. Generally, beneficiaries enrolled in an MA plan providing qualified prescription drug coverage (MA-PD plan) must obtain their prescription drug coverage through that plan.29“
Source: Patricia A. Davis, et al. Medicare Primer. CRS Report R40425. Congressional Research Service: Washington, DC. Updated May 21, 2020.
“In general, individuals who do not enroll in Part B or Part D during an initial enrollment period (when they first become eligible for Medicare) must pay a permanent penalty of increased monthly premiums if they choose to enroll at a later date. Individuals who do not enroll in Part B during their initial enrollment period may enroll only during the annual general enrollment period, which occurs from January 1 to March 31 each year. Coverage begins the following July 1. However, the law waives the Part B late enrollment penalty for current workers who have primary coverage through their own or a spouse’s employer-sponsored plan. These individuals have a special enrollment period once their employment ends; as long as they enroll in Part B during this time, they will not be subject to penalty.30
Individuals who do not enroll in Part D during their initial enrollment period may enroll during the annual open enrollment period, which corresponds with the Part C annual enrollment period—from October 15 to December 7, with coverage effective the following January. Individuals are not subject to the Part D penalty if they have maintained creditable drug coverage through another source, such as retiree health coverage offered by a former employer or union. However, once employees retire or have no access to creditable Part D coverage, a penalty will apply unless they sign up for coverage during a special enrollment period. Finally, for persons who qualify for the low-income subsidy for Part D, the delayed-enrollment penalty does not apply.”
Source: Patricia A. Davis, et al. Medicare Primer. CRS Report R40425. Congressional Research Service: Washington, DC. Updated May 21, 2020.
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Page last updated March 17, 2025 by Doug McVay, Editor.