Medicare
What each part actually covers, the enrolment deadlines that cost money if you miss them, and what a yearly review should look at.
About this coverage
Medicare is federal health coverage, mostly for people 65 and over and for some younger people with certain disabilities. It is not one thing: it is four parts that combine in two broadly different ways, and the choice between those two shapes what you pay and which doctors you can see.
The part that catches people out is timing. Several Medicare deadlines carry a late-enrolment penalty that is added to your premium for as long as you have the coverage — in some cases for life. Getting the dates right is worth more than optimising the plan.
The review tool below sorts out whether your situation is one where a closer look is likely to be worthwhile. It does not choose a plan, and neither does this page.
Medicare Review Tool
Asks what coverage you have now, what prescriptions and doctors matter to you, and classifies whether a coverage review is likely to be worth your time.
Free, and it asks for no contact details.
The four parts
Part A covers inpatient hospital care, skilled nursing facility care, hospice and some home health care. Most people pay no premium for it, having paid in through payroll taxes.
Part B covers doctor visits, outpatient care, preventive services and durable medical equipment. It has a monthly premium, and higher earners pay more through an income-related adjustment.
Part C, Medicare Advantage, is an alternative way to receive Parts A and B: a private plan approved by Medicare, usually with a provider network, often bundling drug coverage and extras.
Part D is prescription drug coverage, sold separately or included in a Medicare Advantage plan. Each plan has its own formulary — the list of drugs it covers — which is why the same prescription can cost very different amounts under different plans.
The two routes, and the difference that matters most
Original Medicare (Parts A and B) lets you use any provider in the country that accepts Medicare, with no network. It has no annual out-of-pocket maximum, which is why many people add a Medigap supplement policy, and Part D for drugs.
Medicare Advantage caps your annual out-of-pocket costs and often bundles drug, dental and vision coverage into one plan, usually for a lower premium. In exchange you use a network, and some services require prior authorisation.
The practical difference for most people is not the premium: it is whether the doctors and hospitals you want are in the network, and whether your prescriptions are on the formulary. Those two checks are worth more than any comparison of headline costs.
One timing point that is easy to miss: the window in which you can buy a Medigap policy without medical underwriting is limited. Outside it, in most states, a supplement can decline you or charge more based on health.
The deadlines
Your Initial Enrolment Period runs for seven months around your 65th birthday — the three months before, the month itself, and the three months after.
If you are still working at 65 and covered by an employer group plan, a Special Enrolment Period may let you delay Part B without penalty. Whether it applies depends on the size of the employer, so this is a question to confirm rather than assume.
Open Enrolment each autumn is when you can change between Original Medicare and Medicare Advantage, or switch drug plans. There is also a Medicare Advantage open-enrolment window early in the year for people already in such a plan.
Miss a deadline without a valid exception and the late-enrolment penalty is permanent for Part B and long-lasting for Part D. Current dates and the exact penalty rules are on Medicare.gov; check them there rather than trusting any summary, including this one.
What a yearly review should check
Plans change every year, and the changes are sent in a notice that is easy to put aside. Four things are worth checking each autumn:
Are your prescriptions still on the plan’s formulary, and in the same cost tier? Are your doctors and hospitals still in the network? Has the premium, deductible or out-of-pocket maximum moved? And has your own health changed in a way that makes a different structure fit better?
A plan that was the right choice last year can quietly become the wrong one without anything happening on your side.
Where this does not help
Worth knowing before you spend time on it.
- This site does not name, compare or recommend Medicare plans. Plan comparison belongs on Medicare.gov, which has the current formularies and networks.
- We cannot tell you whether a specific drug or doctor is covered by a specific plan — that changes yearly and by ZIP code.
- Nothing here determines eligibility, enrolment status or a penalty amount. The Social Security Administration and Medicare decide those.
- If you have Medicaid, Extra Help, or veterans’ benefits, the picture is different enough that general guidance is a poor substitute for advice about your own case.
Common questions
- Do I have to take Part B at 65 if I am still working?
- Not necessarily. If you have coverage through current employment, a Special Enrolment Period may let you delay without penalty — but whether it applies depends on the size of the employer. Confirm it with Social Security before deciding, because the penalty for getting it wrong is permanent.
- Is Medicare Advantage better than Original Medicare?
- Neither is better in general; they fail differently. Advantage caps your annual out-of-pocket costs but restricts you to a network. Original Medicare has no network but no cap either, which is why it is usually paired with a supplement. Which fits depends on your doctors, your prescriptions and how much variability you can absorb.
- What is the drug coverage penalty?
- If you go without creditable prescription drug coverage for a period after becoming eligible, an amount is added to your Part D premium and generally stays there for as long as you have Part D. The current calculation is on Medicare.gov.
- Can I change my mind later?
- Between Medicare Advantage and Original Medicare, yes, during the annual windows. Buying a Medigap supplement later is the harder one: outside your guaranteed-issue window, in most states, it can be medically underwritten.
- Does this site sell Medicare plans?
- This page is educational and names no plan. If you want to talk to a licensed agent about your own situation, the form on this page is how to ask.
Where this comes from
This page is educational. It is not advice, an offer of coverage, or a determination of eligibility or enrolment status.
We are not connected with or endorsed by the United States government, the Centers for Medicare & Medicaid Services, or the Social Security Administration.
Plan availability, costs, formularies and networks vary by location and change each year. Check Medicare.gov for current details.