The first time someone reviews a real Medicare bill, the reaction is usually the same: “Wait, I still have to pay for that?” Medicare is a genuinely valuable program, but it was never designed to cover every dollar of healthcare in retirement. Understanding where the coverage ends is often more useful than memorizing where it begins.
The Four Parts of Medicare in Plain English
Medicare is not one policy. It is four coordinated pieces, and each one covers a different slice of healthcare.
| Part | What it covers | What you typically pay |
|---|---|---|
| Part A | Hospital stays, skilled nursing after admission, hospice | No premium for most; per-admission deductible, coinsurance on long stays |
| Part B | Doctor visits, outpatient care, preventive services | Monthly premium (plus IRMAA at higher incomes), deductible, then 20% with no cap |
| Part C (Advantage) | Bundles A and B, usually drugs plus extras | Plan premium; network and prior-authorization rules |
| Part D | Prescription drugs | Premium; costs vary by formulary and tier |
Part A Covers Hospital Stays
Part A handles inpatient hospital care, skilled nursing facility stays after a qualifying hospital admission, some home health services, and hospice. Most people do not pay a monthly premium for Part A because they paid into it through payroll taxes during their working years. There is still a per-admission deductible, and after a certain number of days, daily coinsurance kicks in.
Part B Covers Doctor Visits and Outpatient Care
Part B is where doctor visits, outpatient procedures, lab work, preventive screenings, and durable medical equipment live. Unlike Part A, Part B carries a monthly premium that adjusts each year, and higher-income retirees pay a surcharge known as IRMAA (Income-Related Monthly Adjustment Amount). After the annual deductible, Medicare typically covers 80% of approved charges, leaving the retiree responsible for the other 20% with no built-in cap.
Part C Is Medicare Advantage
Part C, or Medicare Advantage, is an all-in-one alternative offered by private insurers. These plans bundle Parts A and B, usually include prescription drug coverage, and often add extras like dental, vision, or fitness benefits. In exchange, they use provider networks and prior-authorization rules similar to employer health plans. Advantage plans can lower monthly costs, but they change how you access care.
Part D Covers Prescription Drugs
Part D is standalone prescription drug coverage sold by private insurers. Formularies, tiers, and pharmacy networks vary widely between plans, which is why the “right” Part D plan for one retiree can be a poor fit for a neighbor taking different medications.
What Medicare Does Not Cover
The gaps are where retirement healthcare budgets get uncomfortable. Several categories of care are largely or entirely outside traditional Medicare.
Routine Dental, Vision, and Hearing
Original Medicare does not cover routine dental cleanings, fillings, dentures, eye exams for glasses, most hearing exams, or hearing aids. Some Medicare Advantage plans include limited benefits in these areas, but coverage caps are typically modest compared to actual costs.
Long-Term Custodial Care
This is the biggest surprise for many retirees. Medicare covers short-term skilled nursing after a hospital stay, but it does not pay for extended custodial care such as help with bathing, dressing, or eating. That kind of care, whether at home, in assisted living, or in a nursing facility, falls to long-term care insurance, personal savings, or eventually Medicaid.
Care Outside the United States
Original Medicare generally does not cover care received abroad. Retirees who travel frequently or split time between countries often layer on travel medical coverage or choose a Medigap policy with limited foreign travel benefits.
How Retirees Typically Fill the Gaps
Because Original Medicare has no annual out-of-pocket maximum, most retirees choose one of two paths.
Original Medicare Plus a Medigap Policy
A Medigap (or Medicare Supplement) policy is private insurance that pays some or all of the deductibles, coinsurance, and copayments that Original Medicare leaves behind. Retirees who want broad provider access and predictable costs often pair Parts A and B with a Medigap policy and a standalone Part D drug plan.
A Medicare Advantage Plan
The alternative is to consolidate coverage into a Medicare Advantage plan, which typically includes a built-in out-of-pocket maximum. This can lower monthly premiums, but it also means working within a network and following the plan’s rules for referrals and approvals.
Neither path is universally better. The right structure depends on which providers you want to keep, how often you travel, what medications you take, and how much predictability you want in your monthly budget.
Budgeting for the Costs Medicare Leaves Behind
A realistic retirement healthcare budget usually includes several line items beyond the Part B premium: the Medigap or Advantage premium, the Part D premium, deductibles and coinsurance, dental and vision care, hearing aids if needed, and a reserve for potential long-term care. Studies from Fidelity and the Employee Benefit Research Institute have consistently estimated that a typical retired couple should plan for six figures of healthcare spending over the course of retirement, and that estimate excludes long-term care.
Where IRMAA Fits In
Higher-income retirees pay more for Parts B and D through IRMAA surcharges. Because IRMAA is based on tax returns from two years earlier, income planning decisions made in your early 60s, such as Roth conversions or realized capital gains, can affect your Medicare premiums later. This is one reason healthcare planning and tax planning are hard to separate in retirement.
The Bigger Point
Medicare is a foundation, not a finished roof. Treating it as a complete healthcare solution is what leads to the sticker shock, while treating it as one layer in a broader plan, alongside supplemental coverage, a long-term care strategy, and a healthcare reserve inside your retirement budget, tends to produce far fewer surprises. If it has been a while since you mapped your expected coverage against your expected costs, a mid-year review with your advisor is a good place to start.
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Caitlin John
Caitlin John, LLC is a Private Wealth Management Firm based in Brighton, Michigan. As an Independent Registered Investment Advisor (RIA) firm we work with both individual and institutional investors. Our asset management style focuses on educating our clients on common misconceptions in key areas of investing: true asset class diversification, benchmark correlation, standard deviation and how important risk-adjusted returns are in today’s market environment. As a fee-based assets management firm, educating our clients invokes commitment on their part and accountability on behalf of our Advisors and the firm as a whole.
Our client services extend beyond asset management to provide strategic tax planning and wealth transfer strategies for both retirees and persons preparing for retirement. With our family lineage extending beyond fifty years serving clients, Caitlin John is the culmination of our experience and passion. Our mission is to seek, introduce and deliver the most refined and forward thinking financial strategies and management techniques to our clients. Our foundation of ethics and performance standards are driven by one thing: Stewardship.
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