Last updated: October 19, 2026. This article is for general information only and is not personal financial, insurance, or medical advice. Plans, prices and rules differ by state and ZIP code, so confirm details at Medicare.gov, with your State Health Insurance Assistance Program (SHIP), or with a licensed agent. This guide is not affiliated with Medicare or any insurer.
If you are on Medicare, you have until December 7 to change how you get your coverage for 2027. The biggest decision for many people is whether to stay with Original Medicare plus a Medigap (Medicare Supplement) policy, or to use a Medicare Advantage plan. The short version: Medicare Advantage usually costs less each month but limits you to a plan network and uses prior authorization, while Original Medicare with Medigap costs more each month but gives you the widest choice of doctors and the most predictable bills. The catch is that switching away from Medigap can be hard to undo.
Quick comparison: Medicare Advantage vs Medigap
| Feature | Medicare Advantage (Part C) | Original Medicare + Medigap |
|---|---|---|
| Who runs it | A private insurer approved by Medicare | Medicare pays first; a private Medigap policy pays part of what is left |
| Monthly cost | You still pay the Part B premium, plus any plan premium (many plans charge $0) | Part B premium plus a separate Medigap premium |
| Doctor choice | Usually a network (HMO or PPO) | Any provider in the U.S. that accepts Medicare |
| Yearly spending limit | Yes, an in-network out-of-pocket maximum | No limit in Original Medicare, but Medigap covers most of the gaps |
| Prescription drugs | Most plans include Part D drug coverage | Not included; you add a standalone Part D plan |
| Extras (dental, vision, hearing) | Commonly included | Not included |
| Prior authorization | Common | Rarely needed under Original Medicare |
| Switching later | Easy to switch plans each fall | Insurers may be able to deny you or charge more if you return later |
Key dates for 2027 coverage
- October 15 to December 7, 2026: the annual Medicare open enrollment period. You can switch between Original Medicare and Medicare Advantage, change Advantage plans, or change your Part D drug plan. New coverage starts January 1, 2027.
- January 1 to March 31, 2027: Medicare Advantage Open Enrollment, which is only for people already in an Advantage plan. You can switch to a different Advantage plan or return to Original Medicare (and add a Part D plan).
For this year’s Part D changes, including the deductible and out-of-pocket cap, see our guide to Medicare open enrollment 2027.
How Medicare Advantage works
With Medicare Advantage, a private insurer takes over your Part A and Part B benefits and must cover at least what Original Medicare covers. You still pay your Part B premium. KFF’s analysis of 2026 plans found that about 75% of individual Medicare Advantage plans with drug coverage charged no premium beyond the Part B premium, and the average premium across all enrollees was about $15 a month (including $0 plans). Plans that did charge a premium averaged about $59 a month.
The same analysis found the average in-network out-of-pocket limit for 2026 was about $5,421, while the legal maximum was $9,250. CMS has set the in-network maximum for 2027 at $9,850, according to a summary of its April 2026 final standards; confirm the exact limit for any plan in its Summary of Benefits. Most plans also bundle extras: KFF reported that more than 99% of individual plans offered eye exams or glasses, 98% offered dental coverage and 95% offered hearing benefits, although the amount of coverage varies widely.
The trade-offs to check
- Networks. Your doctors, hospital and specialists must be in the plan’s network, or you may pay more or pay in full. Check each provider on the plan’s own directory, not just a general search.
- Prior authorization. KFF found that 99% of enrollees were in plans requiring prior authorization for some services. In 2024, Medicare Advantage insurers received nearly 53 million prior authorization requests and denied about 4.1 million, or nearly 8%. Many denials are later overturned on appeal, but the process can delay care.
- Costs when you use care. A $0 premium does not mean $0 costs. Look at copays for specialists, hospital stays and drugs, and the plan’s out-of-pocket maximum.
- Travel. HMO plans often cover only emergencies outside the service area. Some PPOs cover out-of-network care at higher cost.
How Medigap works
Medigap policies are sold by private insurers but follow federal standards, so a Plan G from one company covers the same benefits as a Plan G from another. They work only with Original Medicare, and you cannot use Medigap together with a Medicare Advantage plan.
- Plan G is a popular choice for people who first became eligible for Medicare in 2020 or later. It covers most gaps in Original Medicare except the Part B deductible, which was $283 in 2026 according to Medicare.gov.
- Plan N generally has a lower premium than Plan G but you pay copayments of up to $20 for some office visits and up to $50 for emergency room visits that do not lead to admission.
- Plans C and F cannot be sold to people who became newly eligible for Medicare on or after January 1, 2020, because they cover the Part B deductible.
- Prescription drugs are separate. You need a standalone Part D plan. In 2026 the Part D out-of-pocket cap is $2,100.
Medigap premiums depend on your age, ZIP code, the insurer and your tobacco use, and they can rise over time. Compare quotes for the same lettered plan using the Medicare Plan Finder on Medicare.gov or through your SHIP counselor, and ask whether the insurer prices by your age when you buy or by your current age every year.
The Medigap trap: why switching is harder going back
This is the most important point in the whole decision. When you first sign up for Part B at 65 or older, you get a one-time, six-month Medigap Open Enrollment Period. During it, insurers must sell you any Medigap policy they offer at the standard price, regardless of your health. After that window, in most states an insurer can ask health questions and may decline you or charge more.
That means moving from Original Medicare plus Medigap to Medicare Advantage can be a one-way decision. If you later want to return to Original Medicare, you may not be able to buy the same Medigap policy again. A few states, including New York and Connecticut, have more flexible rules, and some others give limited yearly windows, so check your own state’s rules.
There is also a trial right. If you joined Medicare Advantage when you first became eligible and leave within the first 12 months, you may have a guaranteed right to buy a Medigap policy. Ask your SHIP counselor whether this applies to you.
Which one fits you? A simple decision guide
Medicare Advantage may fit if:
- You want a low monthly premium and bundled drug, dental and vision coverage.
- Your doctors and hospital are in the plan’s network and you rarely travel outside the area.
- You are comfortable with prior authorization and with possible copays when you need care.
Original Medicare with Medigap may fit if:
- You want to see any Medicare provider nationwide without network rules.
- You prefer predictable costs and are willing to pay a higher monthly premium for them.
- You spend part of the year in another state or may need specialists at out-of-state hospitals.
- You are healthy enough to qualify for Medigap now and want to keep that option.
A five-step checklist before December 7
- Read your Annual Notice of Change. Your current plan must tell you about changes to premiums, drug lists and networks for 2027, usually by the end of September.
- Re-check every drug. Plans change their formularies each year, so confirm that each prescription is covered and what tier it is in.
- Verify your doctors and hospital in the plan’s directory, and call the office to confirm.
- Compare total yearly cost, not just the premium. Add premiums, expected copays, the drug costs and the out-of-pocket maximum.
- Talk to a free counselor. Your State Health Insurance Assistance Program offers unbiased help. Be cautious of unsolicited calls and ads that promise extra benefits.
Remember the Part B premium and your Social Security check
Whichever route you choose, you pay the Part B premium, which was $202.90 a month in 2026. The 2027 premium has not been officially announced at the time of writing; AARP has cited a Medicare Trustees projection of about $209.50. Most people have the premium deducted from their Social Security payment, which affects how much of the cost-of-living increase reaches their bank account. We walk through the numbers in our Social Security COLA 2027 guide. If you are still working and comparing employer coverage, our HDHP vs PPO guide and the ACA open enrollment 2027 overview cover the other enrollment seasons.
Frequently asked questions
Can I have Medicare Advantage and Medigap at the same time?
No. Medigap works only with Original Medicare. It is illegal for a seller to knowingly sell you a Medigap policy if you are in a Medicare Advantage plan.
Does Medigap include drug coverage?
No. Medigap policies sold today do not cover prescription drugs, so you need a separate Part D plan.
Can I change from Medicare Advantage back to Original Medicare?
Yes, during the fall open enrollment period (October 15 to December 7) or the Medicare Advantage Open Enrollment Period (January 1 to March 31). The difficulty is getting a Medigap policy afterward, since insurers in most states can use medical underwriting.
Is a $0 premium Medicare Advantage plan really free?
You still pay the Part B premium, and you may pay copays, coinsurance and a deductible when you use care, up to the plan’s out-of-pocket maximum.
Bottom line
Medicare Advantage tends to win on monthly cost and extras, while Original Medicare with Medigap tends to win on freedom of choice and predictable bills. Because leaving Medigap can be difficult to reverse, take the time to check your doctors, drugs and total yearly costs before December 7, and use a free SHIP counselor if you are unsure.
Sources: Medicare.gov (Medigap plan benefits chart), KFF (“Medicare Advantage in 2026: Premiums, Out-of-Pocket Limits, Supplemental Benefits, and Prior Authorization”), Kiplinger (Medicare open enrollment guide), BenefitsUSA summary of CMS Contract Year 2027 final standards, AARP (2027 Part B premium projection).
