Medicare Coverage

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If you're approaching Medicare eligibility or already enrolled, one of the biggest decisions you'll face is figuring out which combination of coverage actually makes sense for your situation. Medicare isn't a single plan — it's a system of interlocking parts, and the way you put them together determines what you pay and what's covered. This guide breaks down how the pieces fit together so you can make a confident choice.

The Two Paths: Original Medicare vs. Medicare Advantage

The first decision every Medicare beneficiary faces is choosing between two fundamentally different approaches to coverage. Original Medicare (Parts A and B) is the traditional government-run program — you can see any doctor or hospital that accepts Medicare, anywhere in the country, with no referrals needed. Medicare Advantage (Part C) bundles that same hospital and medical coverage through a private insurer, often adding extras like dental, vision, and hearing benefits.

Neither path is universally better. Original Medicare gives you maximum provider flexibility, while Medicare Advantage plans often have lower out-of-pocket costs and bundled perks — but they come with network restrictions and may require referrals. There are also several types of Advantage plans (HMOs, PPOs, Special Needs Plans) that work differently from each other. Your health, your doctors, and your budget should drive this decision, not marketing.

Agents who walk people through this choice every day tend to lean on a short list of questions rather than a one-size-fits-all answer. "To help someone choose between Medicare Advantage and Medigap, I ask: frequent doctor visits or chronic conditions? Medigap. Want low monthly premiums? Medicare Advantage. Prefer predictable costs? Medigap. Want nationwide coverage and the freedom to keep any doctor? Medigap. Okay with networks? Medicare Advantage. Want drug coverage included? Medicare Advantage. Want one bundled plan? Medicare Advantage. Don't mind piecing it together? Medigap," says Craig Kirscht, a licensed Medicare agent in Colorado. The point isn't that one path is right — it's that the answer comes from how you actually use healthcare.

Filling the Gaps in Original Medicare

If you go the Original Medicare route, you'll quickly notice it doesn't cover everything. There's no annual out-of-pocket maximum, and you're responsible for deductibles, copays, and 20% coinsurance on Part B services with no cap. That's where Medicare Supplement (Medigap) plans come in — they're specifically designed to cover what Original Medicare leaves behind.

That uncapped 20% is the part that catches people off guard. "If a Medicare beneficiary has only Original Medicare, then they could have 20% coinsurance to pay for Medicare Part B approved claims. In 2026 there is no limit to the 20% coinsurance — this could be a large amount. A Medicare Advantage plan will give you a yearly maximum out-of-pocket on the policy, giving you less liability on claims," says Andrew Zurbuch, a licensed Medicare agent in Indiana. A Medigap plan solves the same problem from the other direction, by covering most of that coinsurance directly.

Timing matters here. Your Medigap open enrollment period gives you guaranteed-issue rights to buy any plan regardless of health status, but that window is limited. Outside of it, insurers can deny you or charge more. If you want the security of Medigap, planning ahead is essential — especially if you're transitioning off an employer plan. According to Adam Ashby, a licensed Medicare agent in Colorado, "You should start considering these things 90 days prior to losing your employer's health plan. First of all, you get the gift of guaranteed issue for a Medicare Supplement — this is your once-in-a-lifetime opportunity to be protected by amazing coverage without the need to answer health questions. An agent cannot answer those questions in five minutes. If they do, they are putting you where they want you, not where you necessarily should be."

Prescription Drug Coverage

No matter which path you choose, you'll need to think about prescription drug coverage. Original Medicare doesn't include it, so you'll need a standalone Part D plan. Most Medicare Advantage plans include drug coverage built in. Either way, plans vary widely in which medications they cover and what you'll pay. The old coverage gap (donut hole) works differently now: beginning in 2025, out-of-pocket costs for covered Part D drugs are capped at $2,000 per year, which puts a real ceiling on annual drug spending regardless of which plan you choose. See Medicare.gov's Part D costs page for the current rules.

Don't assume two plans treat the same prescription the same way. "Each Part D plan has its own specific formulary — the list of covered medications. There are also deductibles, copays, and coinsurance that factor in. Whether a particular drug counts toward your coverage gap is much more complicated than yes or no. We need to know the medication, the dosage, and the plan you're enrolled in to give a solid answer," says Mitch Anderson, a licensed Medicare agent in Minnesota. Before locking in a Part D or Medicare Advantage plan, check that every prescription you take is on that specific plan's formulary at a tier you can afford.

What Medicare Doesn't Cover at All

Regardless of how you structure your coverage, some services are generally excluded:

Long-term custodial care
Cosmetic procedures
Care outside the U.S.
Routine vision care under Original Medicare
Dental coverage, which is extremely limited under Original Medicare

For a full breakdown of what each part does and doesn't include, see our guide to understanding what's covered by Medicare.

"I like to say Original Medicare only covers you from the neck down — so no glasses, no dentures, no hearing aids," says Helena Foutz, a licensed Medicare agent in California. "If you want a side of dental and vision with your Medicare, look to a Medicare Advantage plan. Many MA plans offer dental and vision, and it pays to shop around — but let your broker be your personal shopper. It doesn't cost you anything, and they know all the plans." Just be aware that "dental coverage" on an Advantage plan can mean very different things depending on the carrier — some have networks, some are limited annual allowances, and some require you to use specific dentists. Read the benefit details before you assume a plan solves your dental problem.

Understanding Your Costs

Medicare costs aren't just premiums. Between Part B premiums, Part D premiums, deductibles, copays, and coinsurance, your total spending depends heavily on which combination of plans you choose. For a detailed look at every cost component, see our guide to how much Medicare costs in 2026. It's also worth running through a financial checklist to compare your real costs across different scenarios. And be aware that higher income can mean higher premiums — certain Medicare choices can even affect your tax bill.

If cost is a barrier, Medicare Savings Programs can help cover premiums and out-of-pocket expenses for those who qualify.

Enrollment: Don't Miss Your Window

Most people are automatically enrolled when they turn 65, but there are important deadlines beyond that. Missing your enrollment window can result in permanent late-enrollment penalties on both Part B and Part D. For a plain-language breakdown of how those penalties are calculated, Medicare.gov's penalty guide is the authoritative source. Make sure you understand who is eligible and how to enroll before your deadlines arrive. Life changes like losing employer coverage may qualify you for a Special Enrollment Period.

Putting It All Together

The right Medicare coverage isn't one-size-fits-all — it's a combination of parts tailored to how you use healthcare. Whether that's Original Medicare plus Medigap and a standalone drug plan, or a Medicare Advantage plan that bundles everything together, the key is understanding what you're getting and what you're giving up. A local Medicare insurance agent can help you compare the specific plans available in your area at no cost.