Medicare Supplement vs. Medicare Advantage (Part C): What’s the Difference?

Medicare Supplement vs. Medicare Advantage (Part C): What’s the Difference?

Published: September 2, 2025 | Last updated: October 23, 2026

In Short: The main difference is how you pay and which doctors you can see. A Medicare Supplement (Medigap) plan works alongside Original Medicare. It usually has a higher monthly premium but low out-of-pocket costs, and you can see any doctor nationwide who accepts Medicare. A Medicare Advantage (Part C) plan replaces Original Medicare with an all-in-one plan from a private insurer. It often has a lower or $0 premium, an annual out-of-pocket limit, and extras like dental and vision, but it usually uses a provider network.

Let’s talk about Medicare Supplement vs. Medicare Advantage. If you’re feeling confused about whether to choose a Medicare Supplement Plan (Medigap) or a Medicare Advantage Plan (Part C) we’re here to break down the key differences between these two popular Medicare options, so you can decide which one best fits your needs.

Medicare Supplement (Medigap):

A Medigap plan works alongside Original Medicare (Parts A and B) to cover out-of-pocket costs like co-insurance and deductibles.

Key Benefits:
  • Covers Gaps: Helps with co-pays, co-insurance, and deductibles not covered by Original Medicare.
  • No Network Restrictions: See any doctor who accepts Medicare.
  • Guaranteed Renewal: Your plan renews as long as premiums are paid.

Medicare Advantage (Part C):

Medicare Advantage combines Parts A, B, and often Part D (prescription drug coverage) into one plan, offered by private insurers.

Key Benefits:
  • All-in-One Coverage: Combines hospital, medical, and drug coverage in one plan.
  • Predictable Costs: Set out-of-pocket limits to control expenses.
  • Extra Benefits: May include additional perks like dental, vision, and fitness.

What Are the Key Differences Between Medigap and Medicare Advantage?

  • Coverage: Medigap fills gaps in Original Medicare, while Medicare Advantage replaces it with an all-in-one plan.
  • Cost: Medigap has higher premiums but fewer out-of-pocket costs; Medicare Advantage offers lower premiums and an out-of-pocket limit, but may have network restrictions.
  • Flexibility: Medigap allows you to see any Medicare-approved doctor, while Medicare Advantage often requires using in-network providers.

Should I Choose Medicare Supplement or Medicare Advantage?

These are some key questions to think about, but don’t worry if you’re unsure! We can help you answer these questions and make you feel comfortable and confident about your decision.
  • Health Needs: Do you need extra benefits like dental or vision?
  • Budget: Would you prefer a higher premium with Medigap or lower premiums with Medicare Advantage?
  • Provider Flexibility: Do you want the freedom to see any doctor, or are you okay with network restrictions?
Let Us Help You Decide

Choosing the right plan depends on your unique needs. Call us at (803) 256-2067 to speak with a Medicare Account Manager and find the best plan for you!
Watch it all in our YouTube video, linked here: https://www.youtube.com/watch?v=lYl-yKkQoKg

Frequently Asked Questions

Can I have both a Medicare Supplement plan and a Medicare Advantage plan?

No. Medigap plans only work with Original Medicare. If you join a Medicare Advantage plan, a Medigap policy won't pay your costs.

Do Medicare Supplement plans include prescription drug coverage?

No. With a Medigap plan, you'll usually add a separate Part D prescription drug plan. Most Medicare Advantage plans include drug coverage.

Which costs less: Medigap or Medicare Advantage?

Medicare Advantage usually has a lower monthly premium, while Medigap usually has lower costs when you get care. The better value depends on your health, your doctors, and how often you use care.

Can I see any doctor with a Medicare Supplement plan?

Yes. You can see any doctor or hospital in the U.S. that accepts Medicare, with no referrals needed.

Can I switch from Medicare Advantage to a Medicare Supplement plan?

You can return to Original Medicare during certain enrollment periods. In South Carolina, a Medigap insurer may review your health history when you apply outside your guaranteed issue periods, so talk to an agent before you switch.

Does it cost anything to get help comparing plans?

No. Lourie Life & Health's service is at no cost to you.

Still not sure which is right for you? Our local South Carolina agents will compare Medigap (Medicare Supplements) and Medicare Advantage side by side, based on your doctors, prescriptions, and budget. Call (803) 256-2067 or visit one of our offices in Columbia, Greenville, or Myrtle Beach.

Want the full picture? Download our free Medicare Guidebook.