Medicare · Cornerstone
Original Medicare or Medicare Advantage? How to choose, and Medigap vs Advantage
Last reviewed October 12, 202610 min readBy the Goodsurance editorial team Reviewed by the Goodsurance editorial team
Original Medicare or Medicare Advantage is the one Medicare choice that is hard to undo. Many people on Original Medicare add a Medigap plan. So the real question is often Medigap or Medicare Advantage. Neither is better for everyone. Here is the trade, side by side, and the timing rules that decide how easy it is to change your mind.
1The short version
If you only read one part of this page, read this.
The short version
Neither path is better for everyone
Original Medicare with Medigap costs more each month and less when you get care. Advantage is the other way around.
You cannot have Medigap and Advantage together
Medigap only works with Original Medicare.
Your best time to buy Medigap comes once
It is a 6-month window that starts when you are 65 or older and in Part B.
Going back from Advantage can be hard
After that window, a Medigap company can ask about your health in most states. A trial right can protect you in your first year.
2Path one: Original Medicare plus Medigap
You keep Original Medicare (Part A and Part B). Then you add a Medigap policy to pay most of what Medicare leaves, like the 20% you owe for most care. For drugs, you join a separate Part D plan. That is three pieces working together.
What you get is freedom. There is no network. You can see any doctor or hospital in the U.S. that takes Medicare. In most cases you do not need a referral or an approval first. With a full Medigap plan, your bills are small and easy to predict.
What you pay for it is a higher monthly cost. You pay the Part B premium ($202.90 a month for most people in 2026), plus a Medigap premium and a Part D premium. Medigap prices depend on the company, the plan, and where you live.
- Three premiums: Part B, Medigap, Part D
- Higher and steady each month
- Very little when you get care
- Often a low or $0 plan premium
- Copays as you use care
- You pay up to a yearly limit
3Path two: Medicare Advantage
A private plan approved by Medicare gives you your Part A and Part B benefits. Most plans include drug coverage. Some add extras, like dental, vision, and hearing. Some plans have a $0 premium, but you still pay your Part B premium.
What you get is a lower monthly cost and a yearly limit on what you pay for covered care. Once you reach it, you pay nothing more for covered care that year. Original Medicare alone has no such limit.
What you accept is structure. Most plans use a network, so your doctors need to be in it. You may need a referral to see a specialist. You may need approval before some care. In a hard year you also pay copays, up to the plan's limit, and that limit can be several thousand dollars.
No yearly cap in Original Medicare alone. Advantage plans cap your costs each year.
4Medigap or Medicare Advantage: side by side
You cannot have both. Medigap only works with Original Medicare. No one may sell you Medigap while you are in an Advantage plan. The one exception is when you are switching back to Original Medicare. And Medigap cannot pay your Advantage copays or premiums.
So the choice is one or the other. Here is how they compare on the things people care about most.
| Original + Medigap | Medicare Advantage | |
|---|---|---|
| Doctors and hospitals | Any that take Medicare, anywhere in the U.S. | Usually the plan's network |
| Referral to see a specialist | Not needed in most cases | May be needed |
| Approval before care (prior authorization) | Not needed in most cases | May be needed for some services |
| Monthly cost | Part B + Medigap + Part D premiums | Part B + plan premium (some are $0) |
| Yearly limit on what you pay | None in Medicare itself; Medigap pays most gaps | ✓ |
| Drug coverage | A separate Part D plan | Included in most plans |
| Extras like dental, vision, hearing | ✗ | Some plans |
| Emergency care outside the U.S. | Many Medigap plans pay 80% | Usually not; some plans add it |
| Easy to switch to the other later | ✓ | Not always: Medigap may ask about your health |
You cannot have both at once. Sources: Medicare.gov, "Compare Original Medicare & Medicare Advantage" and "Learn how Medigap works."
5The Medigap window that decides your options
Your Medigap Open Enrollment Period lasts 6 months. It starts the first day of the month you are 65 or older and signed up for Part B. You get it once, and it does not repeat.
During those 6 months, any company that sells Medigap in your state must sell you any plan it offers. It cannot charge you more because of your health.
After it ends, in most states there is no promise a company will sell you a policy. If it does, it can charge more because of your health. This is called medical underwriting. A few states give more rights. New York and Connecticut let people buy Medigap all year, and some states have a yearly "birthday rule." Ask your SHIP what your state allows.
Your 6-month Medigap Open Enrollment Period
After month 6: in most states, a company can ask about your health, charge more, or say no.
6Why switching back is hard, and your trial rights
Switching is not the same in both directions. Moving from Original Medicare into an Advantage plan is easy. Going back, from Advantage to Original Medicare plus Medigap, can mean answering health questions.
That matters most when you most want to switch. People often think about leaving Advantage after a health scare. That is just when a Medigap company is most likely to charge more or say no.
Federal law gives you a few ways back without health questions. The biggest one is the trial right. If you try Advantage for the first time, you have one year to change your mind. These rights are listed below. Your state may add more.
Important: most Medigap policies do not cancel on their own when you join an Advantage plan. If you drop Medigap for Advantage and miss your trial right, you may not be able to get it back.
Moving into Advantage is easy. Going back to Original Medicare plus Medigap can mean health questions once your 6-month window has passed. That often happens right when a health scare makes you want to switch.
Your trial rights, and other ways back
You joined Advantage when you first got Medicare at 65
Leave within the first year, and you can buy any Medigap policy sold in your state. Plan C and Plan F are still only for people eligible before 2020.
You dropped Medigap to try Advantage for the first time
Leave within a year, and you can get your old policy back if the same company still sells it. If not, you can buy certain other plans.
Your plan leaves Medicare, or you move out of its area
You get a right to buy certain Medigap plans if you go back to Original Medicare.
Watch the deadline
Apply up to 60 days before your Advantage coverage ends, and no more than 63 days after.
7When you can change plans each year
Open Enrollment, October 15 to December 7. Anyone with Medicare can make a change. You can move from Original Medicare to Advantage. You can go back from Advantage to Original Medicare. Or you can switch plans. Changes start January 1.
Medicare Advantage Open Enrollment, January 1 to March 31. If you are already in an Advantage plan, you can switch to another one or go back to Original Medicare. You can also join a drug plan.
These dates let you change your Medicare path. They do not give you a right to buy Medigap. Say you go back to Original Medicare at some other time. A Medigap company may still ask about your health.
8How your situation changes the answer
There is no winner. There is a better fit for you.
If keeping any doctor and having small, known bills matters most, and you can pay more each month, Original Medicare plus Medigap is built for you. If a low monthly cost and a yearly limit matter most, and you are fine with a network, Medicare Advantage is built for you.
Before you choose, check three things. Are your doctors in the plan's network? Are your drugs on its list? Will you travel or spend part of the year somewhere else? For free, unbiased help, call your State Health Insurance Assistance Program (SHIP) or 1-800-MEDICARE.
If you choose Medigap, Plan G is the most complete plan most new buyers can get. See Medigap Plan G: what it covers, and Plan G vs Plan F.
- You want any doctor, with no network
- You travel or live in two places
- You want small, known bills
- You can pay more each month
- You want a low monthly cost
- Your doctors are in the plan
- You want drugs and extras in one plan
- You are OK with referrals and approvals
Common questions about Medicare
Quick answers to common questions
Tap any question to expand. Each question links to a fuller standalone answer.
Which is better, Medigap or Medicare Advantage?
Neither is better for everyone. Medigap with Original Medicare costs more each month, but you can see any doctor that takes Medicare and your bills are small. Advantage often costs less each month, but uses a network and has copays up to a yearly limit.
Why would I choose Medigap over Medicare Advantage?
People choose Medigap to see any doctor in the U.S. that takes Medicare, to skip referrals and most approvals, and to have small, predictable bills. It also tends to suit people who travel or live in two places.
What is the downside of Medigap?
It costs more each month, and you need a separate Part D plan for drugs. It does not add dental, vision, or hearing. Premiums often go up over time. And outside your 6-month window, a company can ask about your health in most states.
Why do people say not to get a Medicare Advantage plan?
The common worries are networks, referrals, and approvals before care. Another is that going back to Original Medicare and Medigap later can mean health questions. Many people are happy with Advantage. Check your doctors and drugs first.
Is Medicare Advantage more popular than Medigap?
Yes, by count. More than half of eligible people with Medicare are in Advantage. KFF counts 55% of eligible people in 2026 (35.2 million out of 64.2 million with Parts A and B). Popular does not mean right for you.
Can I have Medigap and Medicare Advantage at the same time?
No. Medigap only works with Original Medicare. No one may sell you Medigap while you are in an Advantage plan, unless you are going back to Original Medicare.
When is the Medigap open enrollment period?
It lasts 6 months. It starts the first day of the month you are 65 or older and signed up for Part B. During it, a company cannot turn you down or charge more because of your health.
Can I switch from Medicare Advantage back to Medigap?
You can go back to Original Medicare during Open Enrollment (October 15 to December 7) or, if you are in Advantage, from January 1 to March 31. But a Medigap company may ask about your health unless you have a trial right or another guaranteed right.
What is a Medigap trial right?
If you join Advantage when you first get Medicare at 65, or drop Medigap to try Advantage for the first time, you have one year to switch back. Then you can buy Medigap without health questions.
If I choose Medigap, should I get Plan G or Plan F?
Most new buyers cannot get Plan F. It is only for people eligible for Medicare before January 1, 2020. Plan G is the same except for the Part B deductible. See our Plan G vs Plan F guide.
References
- Medicare.gov: Compare Original Medicare & Medicare AdvantageDoctors, referrals, prior approval, costs, yearly limits, drug coverage, and travel.
- Medicare.gov: Learn how Medigap worksWhy you cannot have Medigap and Advantage together, and the trial right.
- Medicare.gov: When can I buy a Medigap policy?The 6-month Medigap Open Enrollment Period and switching back from Advantage.
- Medicare.gov: Can I change my Medigap policy?Every federal guaranteed issue right, with deadlines.
- Medicare.gov: Joining a planOpen Enrollment and Medicare Advantage Open Enrollment dates.
- Medicare.gov: Get Medigap costsHow Medigap premiums are set, and why they can rise.
- CMS: 2026 Medicare Parts A & B premiums and deductiblesThe 2026 standard Part B premium ($202.90).
- KFF: Medicare Advantage in 2026, premiums and out-of-pocket limitsThe 2026 federal in-network limit and the average plan limit.
- KFF: Medicare Advantage in 2026, enrollment updateThe share of people with Medicare in Advantage plans.
- SHIP: State Health Insurance Assistance ProgramsFree, unbiased Medicare counseling in every state.