Medicare 101
Understand the parts of Medicare, how coverage choices differ, and what to ask before enrolling. Choose a topic below or read through the guide.
Start with the basics
What is Medicare, and who is generally eligible?
Medicare is federal health insurance, generally for people age 65 or older who meet citizenship or residency requirements. Some people qualify earlier because of a disability, End-Stage Renal Disease (ESRD), or ALS. Eligibility depends on your circumstances.
When do people usually become eligible?
For many people, eligibility begins at age 65. Some are enrolled automatically, while others need to sign up. Start learning about the process before your 65th birthday so you have time to check which steps apply to you.
What is Original Medicare?
Original Medicare is made up of Part A and Part B. It is one way to receive your Medicare benefits. You can generally see any doctor or hospital in the U.S. that accepts Medicare. Drug coverage and supplemental coverage are separate decisions.
What is the difference between Medicare and Medicaid?
Medicare is a federal health insurance program. Medicaid is a joint federal and state program that helps eligible people with limited income and resources. They have different eligibility rules. Some people qualify for both, which is called dual eligibility.
Official guidance: Getting started (opens in a new tab) · Parts of Medicare (opens in a new tab)
Part A · Hospital insurance
What is Part A, and what does it cover?
Part A helps pay for inpatient hospital care, skilled nursing facility care, hospice, and certain home health services. Coverage depends on Medicare’s requirements for each service; it does not mean every stay or service is covered.
Official guidance: What Part A covers (opens in a new tab)
Part B · Medical insurance
What does Medicare Part B generally cover?
Part B helps pay for medically necessary services and supplies, along with preventive care. Examples include doctor visits, outpatient services, certain screenings, and durable medical equipment. Each service has its own coverage rules.
What kinds of outpatient and physician services fall under Part B?
Examples can include visits with doctors and other health professionals, outpatient mental health care, and certain ambulance services. Part B may also cover a limited range of outpatient drugs. Ask the provider whether a particular service meets Medicare’s coverage requirements.
Official guidance: What Part B covers (opens in a new tab)
Part C · Medicare Advantage
Another way to receive your Medicare benefits through a Medicare-approved private health plan.
Is Medicare Advantage the same as Part C?
Yes. Medicare Advantage is also called Part C. These plans provide Part A and Part B benefits, and usually include Part D drug coverage.
How does it differ from Original Medicare?
With Medicare Advantage, you receive benefits through a private plan instead of Original Medicare. Costs and rules differ by plan. You may need to use a provider network or obtain approval for certain services.
Can a plan include prescriptions or additional benefits?
A Medicare Advantage plan can include prescription coverage and may offer benefits such as dental, vision, or hearing services. Benefits, limits, provider access, and costs depend on the plan. Always review the specific plan’s documents.
Official guidance: Compare the parts and options (opens in a new tab)
Part D · Prescription drug coverage
Help with the cost of covered prescription medications.
What is Part D, and who offers it?
Medicare Part D is drug coverage offered by private insurance companies approved by Medicare. It helps pay for covered brand-name and generic prescriptions. Plans have their own covered drug lists and pharmacy arrangements.
Can drug coverage be included with Medicare Advantage?
Yes. Many Medicare Advantage plans include drug coverage. People with Original Medicare can join a separate Part D plan. Check how a drug plan would work with your current coverage before making a change.
How do my prescriptions affect plan selection?
Check whether a plan covers your prescriptions, which pharmacies you can use, and what your share of costs may be. Bring questions to your appointment, but do not send medication lists through this website’s forms.
Official guidance: Understanding Part D (opens in a new tab)
Medicare Supplement · Medigap
Supplemental insurance that works with Original Medicare.
What does Medicare Supplement insurance help pay for?
Medigap is private insurance that helps pay some of your share of covered Original Medicare costs, such as deductibles, copayments, and coinsurance. What a policy pays depends on the policy.
Is Medigap the same as Medicare Advantage?
No. Medigap supplements Original Medicare. Medicare Advantage is a different way to receive Medicare benefits. These are different types of coverage and are not interchangeable.
Can I use Medigap with Medicare Advantage?
Medigap cannot be used to pay Medicare Advantage costs. You cannot buy a Medigap policy while you have Medicare Advantage unless you are switching back to Original Medicare. Get help reviewing timing and eligibility before changing coverage.
Is Medigap enrollment the same as annual Medicare enrollment?
No. Medigap has its own enrollment protections and rules. The federal Medigap Open Enrollment Period generally lasts six months, starting when you are at least 65 and enrolled in Part B. Later options may be more limited. Ask about your circumstances before assuming a policy will be available.
Official guidance: Medigap basics (opens in a new tab) · How Medigap works (opens in a new tab)
Understanding enrollment
Timing matters. The right next step depends on your current coverage and personal circumstances.
When should I start thinking about Medicare?
Start before you turn 65. The usual Initial Enrollment Period spans seven months: the three months before your birthday month, your birthday month, and the three months after it. Different rules may apply if you qualify earlier or have other coverage.
What happens when I turn 65?
Some people are enrolled automatically; others must apply. Check your enrollment status and coverage start date rather than assuming coverage begins automatically on your birthday.
What if I am still working at 65?
Employer coverage can affect when you should enroll. Speak with your employer’s benefits administrator and review Medicare.gov’s guidance before delaying enrollment. Late enrollment can cause penalties or coverage gaps in some circumstances.
Can I change plans later? What is the Annual Enrollment Period?
Medicare Open Enrollment, often called the Annual Enrollment Period, runs October 15 through December 7. Eligible changes to Medicare Advantage and drug coverage generally take effect January 1. The changes available depend on your existing coverage. This is not the same as Medigap open enrollment.
Are there other enrollment periods?
Yes. Other periods include General Enrollment, Medicare Advantage Open Enrollment, and Special Enrollment Periods for qualifying circumstances. Each has different rules. Check Medicare.gov or discuss your situation with an agent; this guide is general information, not an individual enrollment recommendation.
Official guidance: When to sign up (opens in a new tab) · Medicare Open Enrollment (opens in a new tab)
Questions to ask before choosing coverage
Start with the care you use, the providers you see, and the costs you want to understand.
Does every plan work with every doctor?
No. Ask both the plan and your providers about participation. When comparing Original Medicare and Medicare Advantage, ask about provider access, referrals, prior authorization, and care when you travel.
Should I compare coverage every year?
An annual review is a useful opportunity to ask what will change for the coming year. Review notices from your plan and ask about your doctors, covered prescriptions, pharmacies, premiums, and other out-of-pocket costs.
What should I ask an agent?
Ask: Are my providers included? How are my prescriptions covered? What could I pay beyond the premium? Are referrals or approvals required? What benefits have limits? When can I enroll or make a change? There is no single type of coverage that is right for everyone.
Official guidance: Review Medicare coverage options (opens in a new tab)
Dental, vision & hearing
Routine care in these areas may call for a closer look at your coverage.
Does Original Medicare normally cover routine dental care?
Original Medicare generally does not cover routine dental care, such as cleanings, fillings, or dentures. Certain dental services connected to covered medical treatment may qualify. Ask your provider about the specific service.
What about routine vision and hearing care?
Original Medicare does not cover routine eye exams for glasses, or hearing aids and exams to fit them. Certain medically necessary eye or hearing services may be covered under separate rules.
Are standalone policies available?
Separate dental, vision, or hearing policies may be available. Some Medicare Advantage plans may include these benefits, too. Ask about availability, waiting periods, benefit limits, and participating providers before choosing coverage.
Official guidance: Dental services (opens in a new tab) · Routine eye exams (opens in a new tab) · Hearing aids (opens in a new tab)
Help with Medicare costs
Some people qualify for programs that help with premiums, prescriptions, or other costs.
What kinds of assistance are available?
Medicare Savings Programs may help eligible people with Part A or Part B costs. Extra Help assists eligible people with Medicare prescription drug costs. Income, resources, and other program rules can affect eligibility.
Can someone have Medicare and Medicaid?
Yes. People who qualify for both are sometimes called dually eligible. Medicaid may help with Medicare costs and other covered services, depending on eligibility and state rules. Contact your state Medicaid office or Medicare.gov for application information.
Official guidance: Help with Medicare costs (opens in a new tab)
Educational content checked against Medicare.gov on September 21, 2026. Coverage and enrollment rules can change. Confirm details with Medicare.gov and the plan’s current documents.
Still Have Questions?
Schedule a conversation with a local licensed insurance agent.