Health Insurance Education Center

Medicare Advantage vs. Medicare Supplement

Two very different approaches to addressing the gaps in Original Medicare. Understanding what Original Medicare actually covers — and what it does not — is the essential starting point for this decision.

Why & The Basics ACA / Marketplace Medicare Advantage & Supplement Medicare Eligibility & Enrollment
Original Medicare Is Not the Same as Medicare Advantage

Before comparing plan options, you must understand what Original Medicare (Parts A & B) is, what it covers, what it does not cover, and how private Medicare plans differ from the federal program itself. These are fundamentally different things.

Federal Program
Original Medicare — Parts A & B

Original Medicare is administered directly by the federal government through the Centers for Medicare & Medicaid Services (CMS). It is divided into two parts:

  • Part A (Hospital Insurance) — covers inpatient hospital care, skilled nursing facility care following a qualifying hospital stay, hospice care, and some home health services.
  • Part B (Medical Insurance) — covers outpatient care, doctor visits, preventive services, lab tests, durable medical equipment, and outpatient mental health services. Part B has a standard monthly premium and annual deductible, plus 20% coinsurance on most covered services with no out-of-pocket cap.
What Original Medicare does NOT include: Routine dental · Routine vision & hearing · Most prescription drugs · No out-of-pocket maximum. In a serious illness year, your financial exposure under Original Medicare alone is not capped.
Private Insurance
Medicare Advantage & Supplement — Private Plans

Medicare Advantage (Part C) and Medicare Supplement (Medigap) are private insurance products — not government programs. They are designed to address the gaps left by Original Medicare, but they operate differently:

  • Medicare Advantage (Part C) — a private plan approved by Medicare that delivers your Part A and Part B benefits through the insurer. You are no longer using Original Medicare directly. Benefits, networks, premiums, and cost-sharing are set by the plan and can change annually.
  • Medicare Supplement (Medigap) — secondary insurance that works alongside Original Medicare. It does not replace Medicare; it pays after Medicare pays, helping cover deductibles, coinsurance, and copayments. You remain on Original Medicare.
Medicare Advantage and Medigap plans are sold by private insurance companies — not administered by the federal government. Plan availability, benefits, and premiums vary by carrier, county, and year and are not guaranteed to remain the same.

How each plan type actually works

Medicare Advantage · Part C
Replaces Original Medicare
Delivered through a private insurer under Medicare contract

A Medicare Advantage plan is an all-in-one alternative to Original Medicare. A private insurance company approved by Medicare delivers your Part A and Part B benefits through the plan — often bundled with Part D drug coverage and additional benefits that vary by plan and location.

  • Bundles Part A and Part B benefits through a private insurer
  • Often includes Part D prescription drug coverage
  • Uses a provider network (HMO or PPO) — provider access varies by plan
  • All MA plans must have an annual out-of-pocket maximum; amount varies by plan
  • Monthly premiums vary by plan, carrier, and location
  • May include additional benefits such as dental or vision — varies by plan
  • Benefits, premiums, and networks can change each year upon contract renewal
  • Cost-sharing (copays, coinsurance) varies by plan and service
Medicare Supplement · Medigap
Works Alongside Original Medicare
Supplements the federal Medicare program — does not replace it

A Medicare Supplement (Medigap) policy is secondary insurance that works alongside Original Medicare. It does not replace Medicare — it pays after Medicare pays, covering some or all of the out-of-pocket gaps such as deductibles, coinsurance, and copayments. Plans are standardized by letter.

  • You remain on Original Medicare — Medigap supplements it
  • Pays after Medicare pays, covering deductibles and coinsurance
  • See any provider nationwide that accepts Medicare — no network
  • No referrals required for specialists
  • Standardized plans (A through N) — same core benefits regardless of insurer
  • Monthly premiums vary by plan letter, insurer, age, and location
  • Does NOT include prescription drugs — requires a separate Part D plan
  • More predictable cost structure once applicable deductible is met

Medicare Advantage vs. Medigap — key differences

FeatureMedicare Advantage (Part C)Medicare Supplement (Medigap)
How it worksReplaces Original Medicare through a private plan approved by MedicareSecondary insurance alongside Original Medicare — does not replace it
Monthly premiumVaries by plan, carrier, and location. Contact me for plan options available in your county.Varies by plan letter, insurer, age, and location. Generally higher monthly premiums than many MA plans.
Part B premiumStill required regardless of MA enrollmentStill required regardless of Medigap enrollment
Provider networkMust use plan's network (HMO/PPO) for covered care in most casesAny Medicare-accepting provider nationwide — no network restrictions
Referrals for specialistsRequired on HMO-type plansNever required
Out-of-pocket maximumAll MA plans are required to have an out-of-pocket cap; specific amounts vary by planVaries by plan letter; some plans cover most costs after the applicable deductible
Prescription drugsPart D often bundled in many plans — varies by planNot included — must purchase a separate Part D plan
Dental, vision, hearingMay be included as additional benefits depending on the specific plan and locationNot included in standardized Medigap coverage
Cost predictabilityCopays per visit vary; costs can accumulate with more frequent care useMore predictable — most costs addressed after meeting the applicable deductible
Annual plan changesBenefits, premiums, and networks can change each year upon contract renewalStandardized letter benefits stay consistent; premiums may change
Travel / out-of-areaEmergency coverage available nationally; routine care generally restricted to local networkWorks with any Medicare-accepting provider anywhere in the U.S.
Important: This table provides general structural information for educational purposes. Actual plan benefits, premiums, and cost-sharing vary significantly by plan, carrier, and county. This is not a description of any specific plan's benefits. Always review the Evidence of Coverage for any plan you are considering. Contact me for plan-specific options available in your area.

Understanding the Medigap plan letters

In most states, Medigap plans are standardized by the federal government and identified by letters A through N. Every insurer offering a given plan letter must provide the same core benefits — the primary difference between carriers is price and customer service. When comparing plans of the same letter, you are comparing prices, not benefits.

A

Core benefits only. Covers Part A coinsurance and hospital costs up to an additional 365 days after Medicare benefits are exhausted. Most limited of the standardized plans.

B

Plan A benefits plus coverage of the Part A hospital deductible. Modest upgrade from Plan A with added inpatient protection.

N

Lower premium than Plan G with modest cost-sharing at time of service (office visits and ER). Offers a balance between monthly cost and coverage. Suitable for those comfortable with some cost-sharing.

F

Most comprehensive — covers the Part B deductible as well. Only available to beneficiaries whose Medicare eligibility date is before January 1, 2020.

C

Similar to Plan F. Also restricted to beneficiaries with a Medicare eligibility date before January 1, 2020.

D

Covers Part A deductible, coinsurance, and skilled nursing facility care. Does not cover the Part B deductible or Part B excess charges.

K

Pays 50% of cost-sharing with a lower annual out-of-pocket limit. Lower monthly premium option for those comfortable with more cost-sharing at point of service.

L

Pays 75% of cost-sharing. Mid-tier option between K and fuller coverage plans. Lower premium with shared costs at time of service.

M

Covers 50% of the Part A deductible. Lower monthly premiums in exchange for partial deductible responsibility. Less common but available in most states.

As a licensed producer, I can compare Medigap pricing across multiple carriers for any given plan letter. Since standardized benefits are identical across insurers for the same letter, finding the most competitive premium is the primary objective. Availability and medical underwriting rules vary by state and enrollment period.

Illustrative examples — not personal recommendations

Individual circumstances vary widely. The scenarios below are illustrative examples only — not recommendations for any specific individual. Your specific health needs, financial situation, preferred providers, and county of residence all affect which option may fit best. These examples should not be relied upon as personal advice.

Medicare Advantage — Illustrative Example
Beneficiary seeking lower monthly premiums with acceptable cost-sharing

A beneficiary on a fixed income who is generally healthy may find that a Medicare Advantage plan offers a lower monthly premium than a Medigap plan. Out-of-pocket costs occur at time of service through copays; the plan's required out-of-pocket maximum provides a cap on annual exposure. Plans vary — review the specific plan's cost-sharing before enrolling.

Actual premiums and cost-sharing vary by plan and county. Network restrictions apply. Review the plan's Evidence of Coverage before enrolling.

Medicare Supplement — Illustrative Example
Beneficiary with ongoing healthcare needs seeking predictable costs

A beneficiary who sees multiple providers regularly, or who has chronic health conditions, may find Medigap's more predictable cost structure beneficial. After meeting the applicable deductible, covered services are largely addressed by the plan — regardless of frequency of care.

Medigap premiums vary by plan letter, insurer, and individual factors. Medical underwriting may apply outside of Medigap Open Enrollment windows.

Medicare Advantage — Illustrative Example
Newly eligible beneficiary who wants coverage bundled in one plan

Someone newly eligible for Medicare who wants drug coverage and other benefits in a single plan may find Medicare Advantage convenient. Many MA plans bundle Part D and may include additional benefits — though specific benefits vary greatly by plan and location. Always confirm what a specific plan includes before enrolling.

Not all MA plans include all benefit types. Network and formulary restrictions apply. Plan benefits change annually.

Medicare Supplement — Illustrative Example
Beneficiary who travels frequently or spends time in multiple states

A beneficiary who spends significant time in different states may find Medigap convenient because it works with any provider that accepts Medicare anywhere in the country — without network restrictions that apply to many Medicare Advantage HMO plans.

Always confirm provider participation in Medicare before seeking care. Coverage rules may differ in specific situations.

CMS Compliance Notice

I am a licensed insurance producer. I am not connected with or endorsed by the U.S. Government or the federal Medicare program. Medicare has neither reviewed nor endorsed this information. This is a solicitation for insurance.

Plans are insured or covered by a Medicare Advantage organization with a Medicare contract and/or a Medicare-approved Part D sponsor. Enrollment in a plan depends on the plan's contract renewal with Medicare. Not all plans available in all areas. Plan benefits, premiums, cost-sharing, and networks vary by plan and location and are subject to change annually.

Medicare beneficiaries may also enroll in Medicare Advantage and Part D plans directly through the CMS Medicare Plan Finder at medicare.gov. Always verify current plan information at Medicare.gov or by calling 1-800-MEDICARE (1-800-633-4227).

Not sure which Medicare plan is right for you?

Let's look at your specific situation together — no pressure, no obligation. A Scope of Appointment will be completed before any Medicare Advantage or Part D plan discussion, as required by CMS.

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