Medicare Advantage Plans (Part C) vs. Original Medicare: How Do You Choose?

A Note on Terms You’ll See Throughout This Guide

What Is Medicare Advantage (Medicare Part C)?

Medicare Part C, better known as Medicare Advantage, is coverage offered by a private insurance company approved by Medicare. It’s a different way of receiving your Parts A, B, and D insurance.

You must have Original Medicare (both Part A [hospital coverage] and Part B [medical coverage]) to enroll in Medicare Advantage.

With Original Medicare, the government pays your doctors and hospitals directly. But under Medicare Advantage, the government instead pays a private insurance company a set amount to manage your care on Medicare’s behalf.

What Does Medicare Part C Coverage Include?

By law, each Medicare Advantage plan must cover all medically necessary care that Original Medicare covers. Most go further, adding:

• Prescription drug coverage (Part D), bundled in rather than purchased separately
• Dental, vision, and hearing benefits
• Fitness memberships or wellness perks
• Transportation assistance to appointments

What Are the Different Types of Medicare Advantage Plans?

Not all Medicare Advantage plans work the same way. Common types include:

• HMOs (Health Maintenance Organizations): Require in-network care and referrals for specialists

• PPOs (Preferred Provider Organizations): Allow out-of-network care at a higher cost—no referrals required

• SNPs (Special Needs Plans): Designed for beneficiaries with specific conditions or circumstances

• MSAs (Medical Savings Accounts): Pair a high-deductible plan with a savings account for medical expenses

• PFFS (Private Fee-for-Service): Sets its own payment terms with providers, outside the standard HMO/PPO structure

You can compare specific Medicare Advantage plan types on Medicare’s website.

Medicare Advantage vs. Original Medicare

When comparing your options, it’s important to look beyond the monthly premium. A plan that costs less while you’re healthy may work very differently when you need ongoing treatment, a specialist, or a hospital stay.

The chart below compares how Original Medicare and Medicare Advantage plans handle different areas of coverage, including provider choice, benefits, and out-of-pocket costs.

Note that these are all general differences. Costs, networks, and coverage rules vary between Medicare Advantage Plans. See Medicare’s website for an in-depth comparison between Medicare Advantage and Original Medicare.

Why Do People Choose Medicare Advantage?

For many beneficiaries, Medicare Advantage offers a desirable combination of lower upfront costs, additional benefits, and streamlined coverage.

Lower Monthly Costs

Monthly costs are often a major consideration in choosing Medicare Advantage. Many plans:

• Charge no premium beyond what you already pay for Part B.
• Keep copays low for everyday visits.
• Include prescription drug coverage.

Annual Out-of-Pocket Maximum

This is one of the biggest differences between Original Medicare and Medicare Advantage.

Original Medicare has no out-of-pocket cap. Without a Medigap policy or other supplemental coverage, a lengthy hospital stay or an expensive course of treatment could leave you responsible for substantial coinsurance with no limit.

Medicare Advantage plans are required to cap what you pay out of pocket each year for Part A and Part B services. Once your copays and coinsurance hit that limit, the plan covers 100% of your remaining covered care for the rest of the year.

Built-in Extras

Medicare Advantage plans frequently add benefits that Original Medicare doesn’t provide on its own, including:

• Dental cleanings
• Vision exams and glasses
• Hearing aids
• Gym/fitness memberships
• Transportation assistance

The specific benefits you have, and what you pay for them, will depend on the plan you choose.

Continuity of Care

If your preferred healthcare providers already participate in a certain plan’s network and you’d like to stay with them, Medicare Advantage may be a practical and convenient fit. However, it’s a good idea to check those providers yearly, since plan details can change over time.

One Card, One Plan

If you have Original Medicare and want to add prescription coverage, you’ll need to enroll in Part D as well as Parts A and B.

Combining medical and drug coverage under a single Medicare Advantage plan and ID card often appeals to beneficiaries who want fewer moving pieces.

What Are the Trade-Offs of Medicare Part C?

Medicare Advantage plans’ lower costs and added perks can come with certain downsides. It’s important to understand them before you enroll.

Provider Networks

Most Medicare Advantage plans fall into one of two types of networks.

HMO plans make up the majority of Medicare Advantage plans. They generally:

• Require you to stay in-network.
• Require a primary care referral before seeing a specialist.
• Only cover out-of-network care in case of emergency.

PPO plans offer more flexibility. PPO networks:

• Prefer in-network specialists.
• Don’t require a referral for specialist visits.
• Allow out-of-network care (usually at a higher cost).
• Have a higher monthly premium (a charge taken directly from the beneficiary’s Social Security, in addition to the Part B premium).

Prior Authorization

Many Medicare Advantage plans require approval before covering certain services, including:

• Advanced imaging, such as MRIs, CT, or PET scans
• Elective surgeries and procedures
• Admission to a skilled nursing facility (SNF)
• Inpatient rehabilitation
• Home health services
• Physical, occupational, or speech therapy beyond a set number of visits
• Durable medical equipment (DME), like wheelchairs, oxygen, or CPAP machines
• Certain specialty or biologic medications
• Some outpatient hospital services

Original Medicare rarely requires this kind of advance approval.

Geographic Limitations

Because coverage is tied to a network, care is usually easiest to access close to home. Beneficiaries who travel often or who split time between two locations sometimes find this limiting.

Why Some Beneficiaries Choose Medigap Instead

Pairing Original Medicare with a Medigap policy (plus a standalone Part D plan) appeals to beneficiaries who value:

• Access to nearly any provider who accepts Medicare
• Little to no concern about staying in-network
• Minimal prior authorization requirements
• Predictable monthly costs, even in a bad health year

The trade-off is a higher monthly premium. In effect, you’re paying more each month to reduce the risk of a costly surprise later.

Medicare Advantage vs. Original Medicare and Medigap: A Sample Year

Who Tends to Choose Medicare Advantage vs. Original Medicare + Medigap?

Medicare Advantage plans often appeal to those who:

• Are generally healthy
• Are managing costs on a fixed income
• Stay within one geographic area
• Are comfortable working within a provider network

Original Medicare with Medigap often appeals to those who:

• Travel frequently
• Want access to major medical centers nationwide
• Are managing complex or multiple health conditions
• Prefer to avoid referrals and prior authorization
• Value predictable costs over flexibility in monthly premiums

Can You Switch to Original Medicare and Buy Medigap Later?

There’s a common misconception: “I’ll switch to Medigap later if I get sick.” This plan doesn’t always work out the way beneficiaries expect.

Medigap enrollment protections vary by state, and in many places, insurers can deny coverage or charge more based on health history if you apply outside your initial enrollment window.

Before enrolling in Medicare Advantage, it’s worth asking:

• How does Medigap enrollment work in my state?
• Could I realistically get supplemental coverage later if I needed it?
• What might premiums look like if I apply at an older age?

For Connecticut Residents

Connecticut residents have an important protection. Under the general federal rule, the easiest time to buy Medigap is usually the six-month Open Enrollment Window that begins when you are 65 or older and first have Part B. In many states, buying a policy after that period can be more difficult.

Connecticut allows Medigap enrollment year-round and provides guaranteed issue protections. That means an eligible CT resident generally cannot be denied a policy due to age or a pre-existing condition. However, you must have Original Medicare to use Medigap, and changes between Medicare Advantage and Original Medicare must follow Medicare’s enrollment rules. Learn more by reading Medicare’s Fact Sheet, “Understanding Medicare Advantage & Medicare Drug Plan Enrollment Periods.”

Ultimately, you should check the timing and available policies before changing coverage. It’s better to take the time to understand the rules before you choose a path, not after a diagnosis changes your circumstances.

Weighing Your Medicare Options

If you’re considering Medicare Advantage, review the providers you want to keep seeing, your prescriptions, the plan’s approval requirements, and its annual out-of-pocket limit. If you’re considering Original Medicare with Medigap, compare the Medigap premium with the costs the policy would cover. A separate Part D plan may be important for prescription coverage; going without Part D or other creditable drug coverage could lead to a late enrollment penalty.

The Right Medicare Choice Depends on You

In summary, Medicare Advantage is generally the lower-premium, managed-care option. Most plans include prescription drug coverage, and many offer additional benefits. However, plan members typically use a provider network and may need prior authorization for certain services.

Original Medicare with Medigap usually has higher monthly premiums. It offers broader access to providers who accept Medicare, fewer prior authorization requirements, and more predictable out-of-pocket costs. Beneficiaries may also need a separate Part D plan for prescriptions.

Neither option is right for everyone. Your decision should account for your preferred doctors, medications, travel habits, health needs, comfort with financial risk, and monthly budget.