Medicare Plan Comparison Chart: Original Medicare vs. Advantage vs. Medigap

When you sit down to choose a Medicare plan for your parent, you quickly discover the system offers dozens of options across at least three separate decision layers. Most online comparisons either oversimplify ("Medicare Advantage has $0 premiums!") or overwhelm ("Here are 47 plans in your county"). Neither helps you make a sound decision.

This post lays out the core Medicare plan comparison in plain language — so you can walk into enrollment season with a clear picture of what each path actually covers, costs, and restricts.

The Three Paths at a Glance

Every Medicare decision flows from one foundational choice: your parent will either use Original Medicare (possibly with supplements) or Medicare Advantage. Everything else builds from there.

The most important number in that table is the out-of-pocket maximum for Original Medicare: none. Without a Medigap supplement, your parent is exposed to unlimited costs. For a parent with cancer or serious heart disease, that 20% coinsurance with no ceiling can mean tens of thousands of dollars in bills.

Medicare Supplement Plans Comparison Chart (Medigap)

If your parent chooses Original Medicare, they need a Medigap policy. The federal government standardizes Medigap — Plan G from AARP covers the exact same benefits as Plan G from Blue Cross. The only differences are price and customer service. Here is how the most relevant plans compare:

Plan G is the right choice for most new enrollees. The math is simple: you pay the $257 Part B deductible once per year, and after that the plan covers everything else Medicare approves. No copays at specialist visits, no coinsurance on surgeries, no daily hospital charges.

Plan N is worth considering for healthy parents who see the doctor infrequently and live in states that ban Part B excess charges (New York, Connecticut, Pennsylvania, Ohio, Massachusetts). The premium savings of $30–$50 per month can outweigh the small copays.

Plan F is only available to those who turned 65 before January 1, 2020. If your parent has it, compare the current premium against a new Plan G — parents with aging Plan F policies often see rapid premium increases as the risk pool ages.

Medicare Advantage Plan Types Compared

Not all Medicare Advantage plans are the same. The structure of the plan determines how much access and cost-sharing flexibility your parent gets.

For most adult children managing a parent's care, an HMO is the riskiest structure if your parent has existing specialists they depend on. Always confirm every current provider is in-network before enrollment — plan directories can be out of date, so call each office directly.

A PPO gives more flexibility but comes with higher out-of-pocket costs when using out-of-network providers. For a parent who travels, sees specialists at academic medical centers, or splits time between states, Original Medicare + Medigap is typically a more practical solution than any MA plan.

The Switching Problem: Why This Chart Matters at Age 65

The comparison above looks balanced — both paths have trade-offs. But there is an asymmetry that makes the decision at age 65 far more consequential than it appears.

Switching from Original Medicare to Medicare Advantage is easy — you can do it during any Annual Enrollment Period (Oct 15 – Dec 7).

Switching back from Medicare Advantage to Original Medicare + Medigap is very difficult once you are past your initial enrollment window. Medigap insurers in most states are allowed to use medical underwriting for applicants who are not in a guaranteed issue period. A parent who develops diabetes, heart disease, or cancer after joining Medicare Advantage may be denied Medigap coverage entirely — or charged premiums that make the policy unaffordable.

The guaranteed issue window opens for 6 months starting when Part B coverage begins. Outside that window, your parent is largely at the mercy of the insurance market.

This is why the plan comparison is not just a budget exercise. It is a long-term risk management decision.

Real Cost Scenarios Side by Side

Numbers clarify what charts cannot. Here is what three different health profiles actually pay in 2026:

Scenario 1: Healthy parent — 1 physical per year, no hospitalizations

• Original Medicare + Plan G + Part D: ~$5,100 total annual cost
• Medicare Advantage (HMO, $0 premium): ~$2,500 total annual cost
• Medicare Advantage saves roughly $2,600

Scenario 2: Moderate health issues — diabetes, heart disease, 5-day hospitalization

• Original Medicare + Plan G + Part D: ~$7,200 total annual cost
• Medicare Advantage: ~$7,300–$7,500 (daily copays, specialist visits, drug costs)
• Roughly equal cost — but Original Medicare offers better specialist access

Scenario 3: Serious illness — cancer, multiple hospitalizations

• Original Medicare + Plan G + Part D: ~$7,200 (premiums + Part B deductible + $2,100 drug cap)
• Medicare Advantage: up to $13,900 (hitting the $9,350 MOOP + Part B premium + drug cap)
• Original Medicare saves nearly $6,700

The pattern is clear: Medicare Advantage wins when your parent stays healthy. Original Medicare wins when your parent gets seriously ill — which becomes more likely over time. Since Medigap becomes harder to obtain as health declines, enrolling in Original Medicare + Plan G at 65 is often the lower-risk strategy over a 20-year horizon.

How to Use This Information Right Now

1. Start with your parent's current doctors. Call each office and ask whether they accept Original Medicare and whether they participate in any specific Medicare Advantage networks in your area. Network access should be the first filter.

2. List all current medications. Use the Medicare Plan Finder (medicare.gov/plan-compare) to run a drug cost comparison across all available Part D plans. Sort by total drug cost + premium, not premium alone.

3. Estimate health utilization honestly. How many specialist visits, procedures, or hospitalizations occurred in the last three years? This gives you the baseline for realistic out-of-pocket modeling.

4. Check your state's Medigap rules. Some states (California, Oregon, Idaho, Illinois, Nevada, Louisiana, Kentucky, Maryland) have "Birthday Rules" that allow switching Medigap plans annually without underwriting. New York, Connecticut, Massachusetts, and Maine allow year-round guaranteed-issue switching. In these states, Medicare Advantage carries less of a one-way-street risk.

5. Use the comparison chart as a discussion tool. Walk through the table with your parent before making any calls. The goal is for them to understand the trade-offs — not just accept whatever an insurance agent recommends.

If you want a structured guide that walks through every step of this decision — including how to use the Plan Finder, how to evaluate prior authorization track records for specific MA plans, and what to ask insurance agents before you trust their recommendation — our Medicare Enrollment Guide covers the full process, step by step.

Medicare plan selection is not a one-time task. Even after your parent enrolls, their plan should be reviewed every year during the Annual Open Enrollment Period from October 15 to December 7. Formularies change. Networks shrink. The "best" plan in 2025 can become the most expensive option in 2026 if their medications move to a higher tier. Set a calendar reminder now and revisit this comparison chart each fall.