What is the best supplemental insurance when on Medicare?

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Plan G is the best and most comprehensive Medicare Supplement (Medigap) plan available for anyone new to Medicare.

Because Medigap plans are standardized by the federal government, a Plan G from one private insurance company offers the exact same core benefits as a Plan G from any other company.

Top Medicare Supplement Plans

  • Plan G (Best Overall for New Enrollees): Covers 100% of your Original Medicare out-of-pocket expenses, leaving you responsible only for the annual Part B deductible.
  • Plan F (Best for Pre-2020 Enrollees): Covers every single out-of-pocket cost, including the Part B deductible. However, it is legally restricted and only available to those who were eligible for Medicare before January 1, 2020.
  • Plan N (Best Value / Budget-Friendly): Offers lower monthly premiums than Plan G, but you must pay small copayments for certain office ($20) and emergency room ($50) visits, plus any Part B excess charges.

Top-Rated Insurance Companies

Because benefits are identical per letter plan, your choice comes down to price, customer satisfaction, and company rate-history. Highly rated providers include:

What is the number one rated Medicare Supplement plan?

There is no single nationally designated "number one" Medicare Supplement (Medigap) plan, because coverage types are standardized by the federal government, but Plan G is currently the most popular and comprehensive plan available to new enrollees.

Standardized Benefits vs. Insurance Companies

Because Medigap benefits are strictly regulated, a Plan G or Plan N from one private insurer offers the exact same basic medical coverage as the same letter plan from another. Instead of a single top plan, major financial and research publications rank the best insurance companies that sell these plans:

  • State Farm: Ranked as best overall by NerdWallet for low customer complaint rates and slow price increases.
  • AARP / UnitedHealthcare: Ranked as best for availability and enrollment size, covering all 50 states.
  • Blue Cross Blue Shield: Top-rated by Forbes Advisor for extra coverage perks and wellness programs.
  • Mutual of Omaha: Known for high financial strength and competitive rates.

Popular Plan Options

  • Plan G: Covers nearly all out-of-pocket costs for Medicare Parts A and B, except for the annual Part B deductible. (Note: Plan F offered slightly more coverage by paying that deductible, but it is closed to anyone newly eligible for Medicare after January 1, 2020).
  • Plan N: Offers lower monthly premiums in exchange for small copays during doctor or emergency room visits.

What supplemental insurance should I get with Medicare?

You need a Medicare Supplement Insurance (Medigap) policy if you want to cover the out-of-pocket costs, like copayments and coinsurance, that Original Medicare does not pay.

What Supplemental Insurance Covers

  • Original Medicare Gaps: Original Medicare (Part A and Part B) covers about 80% of approved medical costs. A Medigap plan helps pay your remaining 20% share.
  • Standardized Benefits: Private insurance companies sell Medigap policies labeled Plans A through N. Plans with the same letter offer the exact same basic benefits, but prices vary by company.
  • Popular Options: Plan G and Plan N are the most common choices for new Medicare members.

What Supplemental Insurance Does Not Cover

  • Prescription Drugs: Medigap policies do not include drug coverage. You must buy a separate Medicare Prescription Drug Plan (Part D) for medications.
  • Routine Care: Medigap plans do not cover dental care, vision exams, eyeglasses, hearing aids, or long-term nursing care.

Do You Need It?

  • Optional Choice: Medigap is optional. If you have other coverage like Medicaid or an employer retiree plan, you may not need it.
  • Alternative Route: You cannot use Medigap if you choose a Medicare Advantage (Part C) plan, which bundles your hospital, medical, and often drug coverage into one private plan.

Do doctors prefer Medigap or Medicare Advantage?

Most doctors prefer Medigap (Medicare Supplement) over Medicare Advantage because it avoids private insurance red tape.

Why Doctors Prefer Medigap

  • Less Paperwork: Doctors bill Original Medicare directly, meaning faster and more predictable payments.
  • No Prior Authorizations: Medigap does not require approval from a private insurance company before giving care. Studies show a vast majority of physicians are frustrated by Advantage plan pre-approval delays.
  • No Network Limits: Patients can see any doctor or hospital nationwide that accepts Medicare.

Why Doctors Dislike Medicare Advantage

  • Administrative Burden: Advantage plans require time-consuming referrals and pre-approvals.
  • Care Denials: Private insurers often delay or deny treatments, which creates friction between the doctor and the patient.
  • Restricted Networks: Doctors must navigate narrow HMO or PPO provider rules set by individual private companies.

What is the average cost of supplemental insurance when you're on Medicare?

The national average cost of Medicare Supplement (Medigap) insurance ranges from $100 to $300 per month, though total costs typically span between $32 and $550+ per month depending on the specific lettered plan and your location.

Average Costs by Popular Plan Type

  • Plan G: Averages $142 to $180 per month; it is the most popular choice for new enrollees and covers all out-of-pocket costs except the Part B deductible.
  • Plan N: Averages $112 to $140 per month; it features lower premiums in exchange for small copayments during doctor or emergency room visits.
  • High-Deductible Plan G: Averages $50 to $55 per month; it requires meeting a $2,950 deductible before benefits apply.
  • Plan F: Averages $185 to $228 per month; it provides comprehensive coverage but is restricted to individuals who were eligible for Medicare before January 1, 2020.

Key Cost Factors

  • Location: State regulations and local healthcare markets heavily influence pricing; monthly state averages can range from under $190 to over $260.
  • Age and Pricing Method: Insurers price policies using community-rated, issue-age-rated, or attained-age-rated methods, meaning premiums may increase as you grow older.
  • Additional Expenses: You must continue paying your standard Medicare Part B premium separately alongside your Medigap premium. You can review options directly through the Official Medicare Guide.

Medigap Plan G vs Plan N (2027): Which Medicare Supplement Is Better for You?

9 related questions found

What is the best insurance to have with Medicare for seniors?

The best insurance to have with Medicare depends on your health needs and budget, choosing between a Medigap (supplemental) policy for maximum doctor choice or a Medicare Advantage plan for bundled extra benefits.

You can learn more about evaluating these choices through the Consumer Reports Guide to Medicare Advantage or the Medicare.org Senior Insurance Overview.

Option 1: Original Medicare + Medigap (Supplement)

  • How it works: You keep government-managed Original Medicare (Parts A and B) and buy private supplemental insurance (Medigap) to pay for things like copays, coinsurance, and deductibles. You also need a separate Part D plan for prescription drugs.
  • Best for: People who want predictable medical bills and the freedom to see any doctor in the U.S. who accepts Medicare without needing referrals.
  • Top providers: Humana and Mutual of Omaha are widely trusted for Medigap plans.

Option 2: Medicare Advantage (Part C)

  • How it works: Private insurance companies replace Original Medicare with an all-in-one plan that bundles Part A, Part B, and usually prescription drug coverage (Part D).
  • Best for: People who want lower monthly premiums and extra perks like dental, vision, hearing, and fitness memberships.
  • Top providers: UnitedHealthcare, Humana, and Aetna lead the market in size, availability, and customer satisfaction ratings.

What is the downside to Medicare Supplement plans?

The main downsides to Medicare Supplement (Medigap) plans are higher monthly premiums, a lack of prescription drug or extra routine benefits, and strict enrollment windows that can lead to coverage denial.

Key Disadvantages

  • Higher Monthly Premiums: Medigap plans require a separate monthly fee in addition to your standard Medicare Part B premium. These rates often rise as you age.
  • No Prescription Drug Coverage: Supplements do not cover outpatient medications. You must buy a separate Medicare Part D plan, which adds another monthly bill.
  • No Extra Routine Benefits: These plans cover medical care only. They exclude routine dental, vision, and hearing care.
  • Medical Underwriting Risks: You have a guaranteed right to buy any Medigap plan without health questions only during your initial 6-month open enrollment window starting at age 65 and enrolled in Part B. Outside this window, insurers can review your medical history and deny coverage or charge more for pre-existing conditions.

What are the top 5 Medicare Supplement plans for 2026?

The top five Medicare Supplement (Medigap) plans for 2026 are Plan G, Plan N, High-Deductible Plan G, Plan F, and Plan K.

Medigap plans are standardized by the federal government. This means a Plan G from one insurance company offers the exact same coverage as a Plan G from another company. Companies only differ by price and customer service.

1. Plan G

  • Coverage: Covers all Original Medicare out-of-pocket costs except the Part B deductible.
  • 2026 Details: You must pay the $283 Part B deductible before coverage begins.
  • Best For: Enrollees who want comprehensive, predictable coverage with minimal out-of-pocket expenses.

2. Plan N

  • Coverage: Covers most gaps like Plan G, but excludes Part B excess charges.
  • 2026 Details: Requires small copayments of up to $20 for some office visits and up to $50 for emergency room visits.
  • Best For: People who want lower monthly premiums than Plan G and do not mind small copays.

3. High-Deductible Plan G

  • Coverage: Operates like Plan G after you meet the annual deductible.
  • 2026 Details: Features a high deductible of $2,950 before the plan begins paying costs.
  • Best For: Budget-conscious individuals who want lower monthly premiums and can handle a higher upfront cost for care.

4. Plan F

  • Coverage: Offers the most comprehensive coverage available, including payment for the Part B deductible.
  • Eligibility Limit: Only available to beneficiaries who were eligible for Medicare before January 1, 2020.
  • Best For: Long-time Medicare beneficiaries who qualified before the cutoff and want first-dollar coverage.

5. Plan K

  • Coverage: A lower-cost, cost-sharing plan that covers 50% of most standard out-of-pocket costs.
  • 2026 Details: Features an annual out-of-pocket limit of $8,000, after which the plan pays 100% of approved costs.
  • Best For: People who want very low monthly premiums and expect low medical usage.

You can review specific benefit breakdowns on the Medicare Compare Plan Benefits page.

What are the biggest mistakes people make with Medicare?

The biggest mistake people make with Medicare is missing enrollment windows, which can lead to permanent financial penalties and coverage gaps.

Timing and Enrollment Mistakes

  • Missing Deadlines: Failing to sign up during your Initial Enrollment Period (IEP) around age 65 triggers lifelong financial penalties for Part B and Part D.
  • Misjudging Work Coverage: Assuming you can delay enrollment while working past 65 without checking if your employer plan is "creditable coverage" (plans with fewer than 20 employees often require Medicare to go first).
  • Missing the Medigap Window: Waiting past your 6-month Medigap Open Enrollment Period (which starts when you turn 65 and enroll in Part B) means you may have to pass medical underwriting to get a supplemental plan.

Plan Choice and Cost Mistakes

  • Focusing Only on Premiums: Choosing a plan with a low or $0 monthly premium without checking deductibles, copays, or maximum out-of-pocket costs.
  • Ignoring Annual Changes: Not reviewing your plan’s Annual Notice of Change (ANOC) or skipping the Annual Enrollment Period, which leads to surprise costs as drug formularies and doctor networks shift yearly.
  • Assuming Doctors are In-Network: Failing to verify if your preferred physicians and hospitals accept your specific Medicare Advantage or Part D network.
  • Thinking Medicare is Free: Forgetting that Original Medicare has monthly premiums, deductibles, and coinsurance, and does not cover routine dental, vision, or hearing care.

Is supplemental insurance worth it when you have Medicare?

Medicare supplemental insurance (Medigap) is worth it for most people because Original Medicare does not have a yearly limit on out-of-pocket costs.

Why Medigap is Worth It

  • No limit on costs: Original Medicare (Parts A and B) covers about 80% of approved medical costs. You pay the remaining 20% coinsurance with no ceiling. A major illness or hospital stay can create massive, unexpected bills.
  • Freedom of choice: You can see any doctor or go to any hospital in the United States that accepts Medicare. You do not need network approvals or referrals to see specialists.
  • No pre-authorizations: Insurance companies do not delay or block medical treatments approved by your doctor.
  • Predictable budget: You pay a steady monthly premium. The plan covers most copays, coinsurance, and deductibles.

When Medigap Might Not Be Worth It

  • High monthly premiums: If you are healthy and rarely see a doctor, paying a high monthly premium plus a separate Part D prescription drug plan may cost more than paying out-of-pocket for occasional care.
  • Medicare Advantage alternative: Some people choose Medicare Advantage (Part C) instead. These private plans bundle services and include a yearly out-of-pocket maximum, but they use strict doctor networks and often require referrals.