Having a clear and practical understanding of Medicare starts with learning the language. Many people researching their Medicare options or searching online for the best Medicare supplement programs are first trying to make sense of unfamiliar terms that appear in Medicare publications, enrollment materials, and plan descriptions.
This glossary defines commonly used Medicare supplement terms and Medigap-related language. It does not compare programs, evaluate options, or recommend specific products.
Medicare-Only Terminology Disclaimer
Important clarification:
The terms defined in this glossary are Medicare and Medigap terms used by the federal Medicare program and private insurance carriers. These terms apply only to Medicare-related programs and do not apply to healthcare sharing ministries or Sharing Programs.
Healthcare sharing ministries, including programs administered by UHSM™, are not insurance and do not coordinate benefits with Medicare or any other payer. Healthcare sharing uses its own distinct terminology, processes, and Membership Guidelines. Click here to learn more about Christian healthcare sharing terms.
This glossary is provided solely for educational purposes to help readers better understand Medicare materials from official and third-party sources.
Medicare and Healthcare Sharing
Some individuals enrolled in Medicare also explore healthcare sharing as a separate, faith-based approach to managing medical expenses. Healthcare sharing ministries operate independently from Medicare and are governed by their own Membership Guidelines. They are not insurance and do not coordinate benefits with Medicare or any other payer.
WeShare® Legacy is a healthcare sharing program administered by UHSM™ for individuals who are enrolled in Medicare and are seeking faith-based sharing support for medical expenses that remain after Medicare processes a service. Medical needs submitted by Members are reviewed according to the program’s Membership Guidelines, and sharing is voluntary and facilitated among Members.
Rather than replacing Medicare, WeShare Legacy is designed to be considered after Medicare, offering an additional layer of sharing support rooted in shared beliefs, transparency, and community. This approach may appeal to individuals who value a Christian-based alternative for addressing eligible medical expenses that Medicare does not fully address.
Learn more about how WeShare Legacy works here.
A – Z Glossary of Key Medicare Supplement Terms
Deductible
In Medicare, a deductible is an amount an individual is responsible for paying for certain Medicare services before Medicare begins paying according to its rules. Original Medicare has separate deductibles for Part A and Part B, and these amounts are established by Medicare and may change annually.
Enrollment periods
Medicare enrollment periods are designated timeframes when an individual may enroll in, change, or disenroll from Medicare-related options. Common enrollment periods include the Initial Enrollment Period, General Enrollment Period, and Annual Enrollment Period. Timing can affect availability, costs, and potential late enrollment penalties.
Guaranteed issue rights
Guaranteed issue rights, sometimes referred to as Medigap protections, are situations defined by federal or state rules in which an individual has the right to purchase certain Medigap policies outside standard enrollment windows. When these rights apply, insurers must offer a policy regardless of health history.
Initial Enrollment Period (IEP)
The Initial Enrollment Period is the first window during which most individuals may enroll in Medicare. It generally begins three months before the month a person turns 65, includes the birthday month, and ends three months afterwards. Enrollment outside this period may be delayed in some situations.
Medigap
Medigap is a commonly used name for Medicare Supplement Insurance. These standardized policies are designed to address certain costs that may remain after Original Medicare processes a service. Standardization varies slightly in Massachusetts, Minnesota, and Wisconsin.
Medicare Advantage
Medicare Advantage, also known as Medicare Part C, refers to Medicare-approved arrangements offered by private companies that deliver Part A and Part B services through a single structure. Some Medicare Advantage options also include prescription drug services.
Medicare assignment
Medicare assignment refers to a healthcare provider’s agreement to accept the Medicare-approved amount as full payment for Medicare services. Providers who accept assignment generally limit additional charges to the individual receiving care.
Medicare SELECT
Medicare SELECT is a type of Medigap policy that requires individuals to use specific hospitals, and in some cases specific providers, to receive full benefits under the policy. These policies follow Medigap standardization rules but may differ in cost due to network requirements.
Medicare Supplement Insurance
Medicare Supplement Insurance refers to standardized Medigap policies that are designed to work alongside Original Medicare. These policies may help address certain expenses that are not fully paid under Original Medicare rules.
Monthly premium
A monthly premium is a recurring amount required by Medicare or a Medicare-related insurance policy to maintain enrollment. Premium amounts vary based on program type, enrollment choices, income-related adjustments, and other factors established by Medicare or insurers.
Original Medicare
Original Medicare is the federally administered Medicare program consisting of:
Part A, which addresses hospital-related services
Part B, which addresses medical and outpatient services
Original Medicare allows individuals to receive services from providers who participate in Medicare.
Out-of-pocket costs
Out-of-pocket costs refer to expenses an individual pays directly when receiving healthcare services under Medicare rules. These may include deductibles, cost-sharing amounts, and charges for services not fully paid under Medicare guidelines.
Part A
Part A is the hospital services component of Original Medicare. It generally relates to inpatient hospital care, skilled nursing facility services, hospice services, and certain home health services.
Part B
Part B is the medical services component of Original Medicare. It generally includes physician services, outpatient care, preventive services, and certain medically necessary supplies.
Part B excess charges
Part B excess charges are amounts a provider may bill above the Medicare-approved amount when the provider does not accept Medicare assignment. Some Medigap policies address these charges, while others do not.
Part C
Part C is another term used to describe Medicare Advantage. It refers to Medicare-approved arrangements offered by private companies that deliver Part A and Part B services.
Part D
Part D refers to Medicare-approved prescription drug services offered through private companies. These may be added to Original Medicare or included within certain Medicare Advantage arrangements.
Plan G
Plan G is a standardized Medigap plan letter frequently referenced when evaluating Medicare Supplement Insurance options. In general, it addresses many cost-sharing amounts that may remain after Original Medicare processes services, except for the Part B deductible.
Plan K
Plan K is a standardized Medigap plan letter that typically addresses a percentage of certain Medicare-approved cost-sharing amounts rather than the full amount. Plans K and L include an annual out-of-pocket limit.
Plan L
Plan L is similar to Plan K but generally addresses a higher percentage of certain Medicare-approved cost-sharing amounts. Once the annual out-of-pocket limit is reached and required Medicare amounts are satisfied, the policy addresses remaining Medicare-approved services for the rest of the calendar year.
Plan N
Plan N is a standardized Medigap plan letter that may involve limited cost-sharing amounts in exchange for different pricing structures. Plan N does not address Part B excess charges.
Medigap Open Enrollment Period
The Medigap Open Enrollment Period is a one-time, six-month period that begins when an individual is both age 65 or older and enrolled in Medicare Part B. During this period, insurers must offer Medigap policies without medical underwriting.
Why Understanding Medicare Supplement Terms Matters
Medicare information often includes detailed and technical language. Understanding Medicare supplement terms can help readers better interpret official resources, ask informed questions, and navigate Medicare materials with greater confidence.
This glossary is provided for educational purposes only and does not offer medical, legal, or financial advice.
Download the full glossary of terms here.
