Medicare Advantage vs. Medigap: The Key Differences Explained
Medicare Open Enrollment runs from October 15 to December 7. It is a good time to look at one of the biggest choices in Medicare: Original Medicare, often paired with a Medigap policy, or a Medicare Advantage Plan.
Neither path is right for everyone. This guide lays out the main differences side by side so you can weigh them for yourself.
The Two Paths in Brief
- Original Medicare is Part A (hospital) and Part B (medical), run by the federal government. Many people add a separate Medigap policy to help with costs and a separate Part D drug plan.
- Medicare Advantage (Part C) is a plan from a private company approved by Medicare. It must cover all medically necessary services Original Medicare covers, and most plans include drug coverage.
One key rule: Medigap works only with Original Medicare. You can’t buy a Medigap policy to go with a Medicare Advantage Plan, according to Medicare.gov.
Doctors and Networks
With Original Medicare, you can see any doctor or hospital in the U.S. that takes Medicare. In most cases, you don’t need a referral to see a specialist.
With Medicare Advantage, you may need to use doctors and hospitals in the plan’s network for non-emergency care. Some plans cover out-of-network care, but it may cost more. You may also need a referral for a specialist, and the plan may require approval before it covers certain services.
Costs and the Out-of-Pocket Limit
Original Medicare usually leaves you paying 20% coinsurance for Part B services after the deductible. It has no yearly cap on what you pay out of pocket. A Medigap policy can help pay costs like that 20%, but it comes with its own monthly premium.
Medicare Advantage Plans have a yearly out-of-pocket limit. Once you reach it, you pay nothing more for covered services that year. Costs vary by plan, and some plans charge a $0 premium. You still pay your Part B premium either way.
Extra Benefits
Original Medicare doesn’t cover some things, such as routine eye exams and most dental care. Many Medicare Advantage Plans offer extras like some vision, hearing, and dental services. What each plan includes differs, so read the details.
Prescription Drugs
With Original Medicare, you join a separate Part D drug plan if you want drug coverage. Most Medicare Advantage Plans already include it, so you typically don’t need a separate plan.
Travel Inside and Outside the U.S.
Original Medicare works with providers who take Medicare anywhere in the country. That can matter if you split your time between states. Plan networks and service areas can limit non-emergency care away from home.
Outside the U.S., neither option generally covers care. Some Medigap policies cover emergency care abroad, and some Medicare Advantage Plans offer emergency and urgent care while traveling as an extra benefit.
Switching Back to Medigap Later
This is the point many people miss. You get a one-time, 6-month Medigap Open Enrollment Period. It starts the first month you have Part B and are 65 or older, and it doesn’t repeat.
During that window, insurers can’t deny you or charge more because of your health. Outside of it, they generally can use medical underwriting. Medicare’s guaranteed issue rights page explains that a company can turn you down if you don’t meet its health requirements.
There are some exceptions, called guaranteed issue rights. The 2026 “Choosing a Medigap Policy” guide describes “trial rights” for people who:
- Joined a Medicare Advantage Plan when first eligible at 65 and want to switch back to Original Medicare within the first year.
- Dropped a Medigap policy to try Medicare Advantage for the first time and want to return within the first year.
Deadlines apply to these rights, and states may add more protections. Before leaving a Medigap policy or choosing Medicare Advantage, check with your State Insurance Department or a SHIP counselor about what would happen if you wanted to switch back.
How Open Enrollment Fits In
From October 15 to December 7, Medicare.gov says you can:
- Switch from Original Medicare to a Medicare Advantage Plan, or the other way around.
- Join, drop, or switch Medicare Advantage Plans.
- Join, drop, or switch Part D drug plans if you have Original Medicare.
Changes start January 1. The plan must get your request by December 7. If you’re already in a Medicare Advantage Plan, there is another window from January 1 to March 31 to switch plans or return to Original Medicare.
Keep in mind that Open Enrollment does not change the Medigap underwriting rules above. Returning to Original Medicare doesn’t guarantee you can buy a Medigap policy.
Where to Get Free, Unbiased Help
- Read your plan’s “Annual Notice of Change” to see what is changing for 2027.
- Compare plans, costs, and networks with the Medicare Plan Finder.
- Call 1-800-MEDICARE (1-800-633-4227), available 24 hours a day. TTY users can call 1-877-486-2048.
- Contact your local SHIP through shiphelp.org. SHIP counselors offer free, confidential, one-on-one Medicare help.
Be cautious with anyone who calls out of the blue to sell a plan or asks for your Medicare number. When in doubt, hang up and call 1-800-MEDICARE yourself.
More on Seniors Tips
- Medicare Open Enrollment 2026: A Step-by-Step Guide to Reviewing Your Coverage
- Medicare Open Enrollment Scams: Red Flags and What to Do
- Does Medicare Cover You When You Travel Abroad?
