The Four "Corners" of Medicare

Medicare is made up of four main parts, each offering different types of coverage: Part A, Part B, Part C, and Part D. Here’s a quick look at how each “corner” of Medicare works to cover your healthcare needs.

Medicare Part A and Part B: “Original Medicare”

• Medicare Part A covers hospital-related expenses and is managed by Medicare. It includes:

  • Inpatient hospital care

  • Stays in most skilled nursing facilities

  • Hospice and some home health services

Most people don’t pay a premium for Part A if they (or their spouse) paid Medicare taxes while working, qualifying them for “premium-free Part A.” You’re eligible for this if:

• You’re already receiving Social Security or Railroad Retirement Board benefits

• You qualify for Social Security or Railroad benefits but haven’t filed for them yet

• You or your spouse held Medicare-covered government jobs

• If you’re under 65, you may qualify if you’ve been on disability benefits for 24 months or if you have End-Stage Renal Disease (ESRD) and meet specific criteria.

• Medicare Part B covers medical expenses, also managed by Medicare. It provides coverage for:

  • Doctor visits, clinical lab services, and outpatient care

  • Preventive services, screenings, and certain supplies

  • Physical and occupational therapy

Together, Part A and Part B make up “Original Medicare,” providing essential hospital and medical coverage.

Medicare Part C: “Medicare Advantage”

Medicare Advantage (Part C) is an alternative way to receive Medicare Part A and Part B benefits. Medicare Advantage Plans, offered by private companies approved by Medicare, combine hospital and medical coverage in one plan and often include extra benefits like vision, dental, and hearing. These plans can also incorporate Part D (prescription drug coverage) as Medicare Advantage Prescription Drug (MA-PD) Plans. Common types of Medicare Advantage Plans include:

• Preferred Provider Organizations (PPO)

• Health Maintenance Organizations (HMO)

• Private Fee-for-Service (PFFS)

Medicare Advantage plans vary by location, often available in specific counties or regions rather than nationwide. They have their own rules for eligibility, enrollment, and using in-network providers, which may require you to choose a Primary Care Physician or use network providers for certain services.

Medicare Part D: Prescription Drug Coverage

Medicare Part D offers prescription drug coverage and can be added to Original Medicare through a stand-alone Prescription Drug Plan (PDP). Many Medicare Advantage plans also include prescription drug coverage, known as Medicare Advantage Prescription Drug (MA-PD) plans.

With Medicare’s four “corners” in place, you have options to tailor coverage that best fits your healthcare needs. Original Medicare (Parts A and B) covers core hospital and medical expenses, while Medicare Advantage (Part C) and Part D add flexibility with comprehensive or specialized coverage options, including prescription drugs.