What Is Medicare and Who Qualifies? A Complete Guide
Medicare isn't one plan: it's four pieces that combine in different ways. Understanding those pieces is the difference between overpaying for years and having the right coverage from day one.
Updated on September 1, 2026 · 8 min read
The four parts, in plain English
Each part covers something different:
- Part A (hospital): inpatient stays, skilled nursing care, hospice. For most people there's no premium because it was already paid through payroll taxes.
- Part B (medical): doctor visits, tests, ambulance, medical equipment. It has a standard monthly premium.
- Part C (Medicare Advantage): a private plan that bundles A and B, almost always with D, plus extras like dental, vision and transportation.
- Part D (prescriptions): drug coverage, either standalone or included in an Advantage plan.
Who qualifies
You qualify if you're a citizen or a lawful resident with at least 5 continuous years in the country, and you also meet one of these:
- You're 65 or older.
- You're under 65 and have received Social Security disability benefits for 24 months.
- You have end-stage renal disease (ESRD) or ALS (with ALS, coverage starts immediately).
When to enroll and what happens if you wait
Your Initial Enrollment Period lasts 7 months: the 3 months before the month you turn 65, your birthday month, and the 3 months after. Enrolling in the first 3 months avoids delays in your start date.
If you're still working and have active employer coverage, you can delay Part B without a penalty using a Special Enrollment Period once that job or coverage ends.
The late Part B penalty is an extra 10% on the premium for every 12 months you could have enrolled and didn't, and you pay it for life. The Part D penalty is 1% of the national base premium for each month without drug coverage.
What Medicare costs
Reference points for budgeting; exact figures change every year, and higher-income beneficiaries pay an additional adjustment (IRMAA).
| Item | Typical cost | Note |
|---|---|---|
| Part A | $0 for most people | With 40 quarters of work history |
| Part B | Standard monthly premium | Deducted from Social Security |
| Part C (Advantage) | From $0 extra | Many plans in Houston and Katy have a $0 premium |
| Part D | Varies by plan | Choose based on your medications, not the premium |
Advantage or Medigap: the key decision
An Advantage plan usually has a low premium, a provider network and extras, with copays when you use services. A supplement (Medigap) costs more each month but covers nearly everything Medicare leaves open and lets you see any doctor who accepts Medicare, with no referrals.
Timing is the critical part: during the first 6 months of your Part B you have a guaranteed right to buy a Medigap plan with no health questions. After that, in Texas, the insurer can turn you down.
Questions we hear often
Does Medicare cover dental and vision?
Original Medicare doesn't cover routine dental or vision. Many Medicare Advantage plans do include those benefits, with annual limits.
Can I have Medicare and a Marketplace plan at the same time?
It isn't advisable: once you're eligible for Medicare you lose the Marketplace subsidy. The right move is to transition when your Medicare starts.
Do I need Part D if I don't take medications?
Yes, it's recommended. Without drug coverage you accumulate a lifetime penalty, and a basic plan usually costs far less than that penalty.
What does the agent charge to help me?
Nothing. Our guidance is free in English and Spanish; insurers compensate us and the plan price is the same as if you enrolled on your own.