Medicare basics: what families should know

Medicare is the federal health insurance program for people 65 and older and some younger people with disabilities. This page explains the pieces in plain English, the deadlines that cause lifelong penalties, and where to get free, unbiased help.

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The parts of Medicare

These descriptions come from Medicare.gov:

Two main ways to get Medicare: Original Medicare (Parts A and B, with any doctor or hospital that takes Medicare, plus an optional drug plan and optional Medigap), or a Medicare Advantage Plan. Which is better depends on the person. A free SHIP counselor can go over your parent’s situation.

When to sign up or make changes

Missing a window can mean waiting months and paying a penalty for life. Medicare.gov lists these periods:

PeriodWhenWhat you can do
Initial Enrollment PeriodGenerally 7 months: starts 3 months before the month you turn 65 and ends 3 months after it.Sign up for Part A and Part B. You can also join a Medicare Advantage Plan or a drug plan.
General Enrollment PeriodJanuary 1 to March 31 each year.Sign up for Part B (and premium Part A) if you missed your first chance. Coverage starts the month after you sign up. A late penalty may apply.
Special Enrollment Period (job coverage)Up to 8 months after the job or the job-based coverage ends, whichever happens first.Sign up for Part B without a penalty if you (or your spouse) had health coverage from current work. COBRA and retiree coverage don’t count.
Open Enrollment PeriodOctober 15 to December 7 each year.Join, switch, or drop a Medicare Advantage Plan or drug plan, or switch between Original Medicare and Medicare Advantage. Changes start January 1.
Medicare Advantage Open Enrollment PeriodJanuary 1 to March 31 (only if you’re already in a Medicare Advantage Plan), and within the first 3 months you have Medicare.Switch to another Medicare Advantage Plan, or go back to Original Medicare and join a separate drug plan.
Medigap Open Enrollment Period6 months, one time only, starting the first month you have Part B and are 65 or older.Buy any Medigap policy sold in your state. Companies can’t refuse you or charge more because of health problems. After it ends, you may be turned down or pay more.

There are other Special Enrollment Periods, for example after a move, after losing Medicaid, or when you get Extra Help. Use Medicare.gov’s pages on when coverage starts and joining a plan, or ask a SHIP counselor.

Late enrollment penalties

Medicare.gov says late penalties are added to the monthly premium, aren’t a one-time fee, and for most people last as long as they have that coverage.

Still working, or covered by a spouse’s job? Talk to the employer’s benefits office and a SHIP counselor before you delay Part B. Medicare.gov says COBRA and retiree coverage don’t give you a Special Enrollment Period.

Help paying Medicare costs

What Medicare doesn’t cover

Medicare.gov says Medicare doesn’t pay for long-term care, meaning help with everyday tasks like bathing and dressing, at home, in assisted living, or in a nursing home. It covers only short-term skilled nursing facility care and part-time home health care when certain conditions are met. See paying for long-term care.

Scams: protect the Medicare number

Medicare.gov says Medicare will never call you to sell you anything or visit you at your home. Medicare, or someone representing Medicare, will only call and ask for personal information in limited situations, like returning a call after you joined a plan, reported fraud, or left Medicare a message.

Medicare.gov’s tips to prevent fraud and medical identity theft:

Report suspected fraud to 1-800-MEDICARE (1-800-633-4227) or online at Medicare.gov. For a Medicare Advantage or drug plan, Medicare.gov also lists the I-MEDIC at 1-877-772-3379. Your state’s Senior Medicare Patrol, funded by ACL, can help you spot and report fraud: smpresource.org or 1-877-808-2468. Already gave out a number? See identity theft and scam calls.

Free, unbiased help

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Sources

Last checked Oct 18, 2026.

  1. Medicare.gov: Parts of Medicare: https://www.medicare.gov/basics/get-started-with-medicare/medicare-basics/parts-of-medicare
  2. Medicare.gov: What's Medicare Supplement Insurance (Medigap)?: https://www.medicare.gov/health-drug-plans/medigap
  3. Medicare.gov: Medigap, get ready to buy (Medigap Open Enrollment Period): https://www.medicare.gov/health-drug-plans/medigap/ready-to-buy
  4. Medicare.gov: When does Medicare coverage start? (enrollment periods): https://www.medicare.gov/basics/get-started-with-medicare/sign-up/when-does-medicare-coverage-start
  5. Medicare.gov: Joining a plan (Open Enrollment, Medicare Advantage Open Enrollment, SHIP): https://www.medicare.gov/basics/get-started-with-medicare/get-more-coverage/joining-a-plan
  6. Medicare.gov: Avoid late enrollment penalties: https://www.medicare.gov/basics/costs/medicare-costs/avoid-penalties
  7. Medicare.gov: Medicare Savings Programs: https://www.medicare.gov/basics/costs/help/medicare-savings-programs
  8. Medicare.gov: Help with drug costs (Extra Help): https://www.medicare.gov/basics/costs/help/drug-costs
  9. Social Security: Apply for Part D Extra Help: https://www.ssa.gov/medicare/part-d-extra-help
  10. Medicare.gov: Long-term care coverage: https://www.medicare.gov/coverage/long-term-care
  11. Medicare.gov: Reporting Medicare fraud & abuse: https://www.medicare.gov/basics/reporting-medicare-fraud-and-abuse
  12. Senior Medicare Patrol National Resource Center (supported by ACL): https://smpresource.org/
  13. SHIP National Technical Assistance Center: find your local SHIP: https://www.shiphelp.org/
  14. ACL: State Health Insurance Assistance Program (SHIP): https://acl.gov/programs/connecting-people-services/state-health-insurance-assistance-program-ship
  15. Medicare.gov: Plan Finder: https://www.medicare.gov/plan-compare/

Rules and numbers change. If something here does not match what an agency tells you, trust the agency, and please let us know.