Medicare Parts A and B Explained

Medicare is our nation’s health insurance program for people age 65 or over or receiving Social Security Disability benefits. Medicare covers most medically necessary services and supplies.

Medicare Advantage plans offer another way of accessing Medicare benefits; many also include prescription drug coverage as part of this option.

Part A

Medicare Part A covers inpatient hospital stays at critical access hospitals and skilled nursing facilities as well as skilled nursing facilities, hospice care and home health services. You may enroll at any time after becoming eligible. There’s no premium associated with Part A if either you or your spouse has paid Social Security taxes for at least 10 years; however a premium for Medicare Part B will apply if enrolling during an Initial Enrollment Period or General Enrollment Period (GEP).

GEP (General Enrollment Period) occurs from January 1 through March 31 each year and offers Medicare beneficiaries an opportunity to sign up for Part B or premium Part A during this time. If they decide later on to change, any penalties they incur for doing so could extend for life – so make sure that when signing up during this period that premium Part A/Part B enrollment occurs before March 31.

If you don’t enroll during your initial enrollment period (IEP), CMS-L564 gives you access to a special enrollment period (SEP). With an SEP you can sign up for premium Part A or Part B coverage due to misrepresentations or reliance on information from employers/group health plans/agents/brokers of health plans/or any other entity not approved by Medicare.

Traditional Medicare (Parts A & B) charges an monthly insurance premium based on your enrollment date and income. You’ll also have to pay a deductible and coinsurance for every service, though supplemental coverage such as Medigap may help cover additional expenses.

Medicare Advantage Plans (Part C) are private health plans that offer an alternative way of accessing your medical and drug coverage. These cost-effective “bundled” plans combine Part A, B and D into one cost-efficient package that typically has lower monthly premiums than traditional Medicare. Many Advantage plans also include extra benefits like vision, hearing, dental and prescription drug coverage as well as annual out-of-pocket caps or mandates to use providers from their network.

Part B

Medicare Part B covers a range of doctor visits, outpatient care services and durable medical equipment (like wheelchairs). Medicare also covers preventive services like vaccinations and annual check-ups as well as diagnostic tests such as MRIs, CT scans and EKGs as well as mammograms for female beneficiaries aged 40 or above.

If you enroll in traditional Medicare plans, Part B premiums will depend on your lifetime earnings. Furthermore, certain services may require you to pay additional deductibles or coinsurance charges; you can purchase a Medigap policy to help reduce out-of-pocket expenses.

Your Medicare Part B enrollment period must fall during a specific time frame to avoid paying a penalty, usually eight months prior to, during, and three months post 65th birthday. There may also be special enrollment periods which provide opportunities. These could include:

During the Initial Premium Payment Period (IPPE), you’ll pay both your Medicare Part B monthly premium and any applicable Medicare Part D prescription drug coverage premiums. Once IPPE concludes, your monthly Part B premiums will remain steady.

Most Medicare recipients don’t owe a Part B deductible because they (or their spouse) have paid Social Security taxes for at least 40 quarters, or 10 years. But if you do not earn enough credits through work or are not covered by worker’s compensation insurance from your spouse’s job, then a monthly Part B premium ($311, $565 in 2026) plus late enrollment penalty must be paid each month.

If this describes your situation, complete the CMS-40B Application for Medicare Part B Enrollment (PDF). You can do it online or over the phone from 8 am to 7 pm ET Monday through Friday in English or Spanish. Alternatively, contact your State Health Insurance Assistance Program (SHIP), available across most U.S. time zones; for one-on-one guidance you can call them anytime for guidance and help navigating Medicare options.

Part C

Medicare Advantage (Part C), is an alternative to Original Medicare that combines hospital and doctor coverage (Parts A and B), prescription drug coverage (Part D) as well as extra benefits like dental, vision and hearing protection – often through private insurers approved by Medicare – into one plan offered by private insurers approved by Medicare.

Medicare Advantage plans come in all varieties – HMOs, PPOs and managed care plans of various sorts are available – from HMOs and PPOs to other managed care models that may offer low or no monthly premiums; others require copays for non-emergency services or may need referrals in order to see specialists.

Each Medicare Advantage plan comes with its own rules about choosing doctors and hospitals, selecting services needed, and setting cost limits on care. When selecting your Medicare Advantage Plan it should meet both your lifestyle needs as well as budget restrictions.

Medicare Advantage plans often come equipped with extra benefits that go beyond basic coverage, including fitness programs, health and wellness benefits and discounts on healthy products. Some plans even provide free membership at select gyms as well as access to online fitness classes and in-home personal training sessions – and often for free!

Medicare Advantage plans also feature their own network of doctors and hospitals contracted with by the insurance company in order to provide you with care, known as preferred provider organizations (PPOs) or health maintenance organizations (HMOs). You will generally be required to use providers within this network except in emergency cases; most plans have an out-of-pocket limit which prevents you from exceeding an established amount during a year.

If you choose a Medicare Advantage plan, you’ll have the freedom to decide whether or not you wish to include a Medicare Part D prescription drug plan. Some plans offer low or no monthly premiums while others require you to meet deductibles and copays for services like doctor visits and hospital stays.

At this point, you can sign up or switch your Medicare Advantage plan during the Open Enrollment Period between January 1 and March 31 of every year, or qualify for an individual Special Enrollment Period depending on your unique situation.

Part D

Part D stands apart from Parts A and B by being managed privately through companies under contract with Medicare to offer prescription drug coverage through insurance plans regulated and subsidised by them on an annual basis. Part D provides comprehensive prescription drug coverage to Medicare beneficiaries, with monthly premiums, annual deductibles, co-payments/co-insurance for specific drugs and a gap phase that reimburses 75% of certain covered costs once beneficiaries reach their plan’s catastrophic limit. There are various kinds of Part D plans available – some stand-in standalone plans while others come as part of Medicare Advantage Plans or from private insurers – offering full or partial coverage depending on individual beneficiary circumstances.

Medicare Advantage Plans (MA) offer hospital and medical coverage with Part D benefits through an expansive network of health care providers. Some MA plans are managed care plans, which typically contract with doctors and hospitals to deliver care; others are private fee-for-service (PFFS) plans; there are even Special Needs Plans (SNP), designed specifically for individuals living with chronic or disabling conditions.

People typically can join or switch Medicare Advantage and Part D plans during the Annual Election Period (AEP), which runs from October 15 to December 7. In certain circumstances, they may also qualify for a Special Enrollment Period (SEP), allowing them to enroll or switch plans outside the AEP window.

People may lose their Part D coverage voluntarily if they go 63 days or longer without creditable drug coverage after the IEP enrollment period has closed; once informed of this development, they can enroll in another Part D plan during LIS SEP enrollment period.

At Medicare’s open enrollment period, members should carefully evaluate all of their options to find a plan tailored specifically to their needs. It is advised that people review their prescription drug needs as well as premium costs during this timeframe. Beneficiaries should make sure any new plan will cover their medications at an affordable price by factoring in annual deductible costs and out-of-pocket expenses associated with prescribed drugs. Beneficiaries who are having difficulty finding a suitable plan might want to request formulary exception from their physician to assist in paying for expensive drugs not on preferred lists of preferred prescription medication lists.