Medicare Basics 2026 — everything in plain English.

1. What is Medicare?

Medicare is the federal health insurance program for people 65 and older — and for some people under 65 with specific disabilities or End-Stage Renal Disease (ESRD). It's been around since 1965.

Most people become eligible the month they turn 65. If you've worked at least 10 years (40 quarters) paying Medicare taxes, you (or your spouse) get Part A premium-free. Part B has a monthly premium.

Medicare is not the same as Medicaid. Medicare is age/disability-based federal coverage; Medicaid is income-based, jointly run by states. Some people qualify for both — they're called "dual-eligibles" and have the most generous coverage available.

2. The four parts of Medicare: A, B, C, D

Medicare has four parts that work together. Many people get confused because the lettering doesn't follow obvious logic.

Part A — Hospital Insurance

Inpatient hospital stays, skilled nursing facility care after a hospital stay, hospice, and some home health care. Most people pay $0 premium for Part A. The 2026 inpatient deductible is $1,736 per benefit period.

Part B — Medical Insurance

Doctor visits, outpatient care, preventive services, durable medical equipment, mental health, lab tests. Standard 2026 premium is $202.90/mo (more if your income is above $106k single / $212k joint due to IRMAA). $283 annual deductible, then you pay 20% of most services with no cap.

Part C — Medicare Advantage

A private bundle that combines Parts A + B (and usually D) into one plan. Must cover everything Original Medicare covers. Often includes extras (dental, vision, hearing, OTC card, fitness). Networks (HMO/PPO). Often $0 premium.

Part D — Prescription Drug Coverage

Standalone drug plans that pair with Original Medicare or Medigap. Each has its own formulary and pharmacy network. 2026's biggest change: a brand new $2,000 annual out-of-pocket cap on covered drugs.

3. Medigap (Medicare Supplement)

Medigap is the fifth piece. It pairs with Original Medicare (A+B) to fill the 20% gaps. Plan G is the most popular — covers everything except the $283 Part B deductible. Plan N is the second most popular — slightly less coverage, $30–60/mo cheaper.

Medigap is sold by private carriers but standardized by federal rules. A Plan G is a Plan G no matter which carrier you buy from — only the price varies.

Critical: Medigap is medically underwritten in most states outside your initial 6-month Open Enrollment Period (starts when you turn 65 + enroll in Part B). If you wait, you may be denied coverage based on health.

4. Enrollment windows

Multiple Medicare enrollment windows exist. Missing the right one can cost you penalties for life.

• Initial Enrollment Period (IEP): 7 months around your 65th birthday — 3 months before, your birthday month, 3 months after.
• General Enrollment Period (GEP): Jan 1 – Mar 31 each year. For people who missed their IEP. Late penalty applies.
• Annual Enrollment Period (AEP): Oct 15 – Dec 7. Switch MA or Part D plans for next year.
• Medicare Advantage OEP: Jan 1 – Mar 31. MA members can switch MA plans once or return to Original Medicare.
• Special Enrollment Periods (SEP): Year-round, triggered by qualifying events (move, loss of employer coverage, gain Medicaid, plan exits area).

5. 2026 costs at a glance

• Part A premium: $0 for most (worked 10+ years).
• Part A inpatient deductible: $1,736 per benefit period.
• Part B standard premium: $202.90/mo (more if income > $106k single / $212k joint — IRMAA).
• Part B annual deductible: $283.
• Medigap Plan G premium: $130–$220/mo depending on age, gender, state, carrier.
• Part D plan premium: $0–$80/mo depending on plan.
• Medicare Advantage premium: Often $0/mo (you still pay Part B).
• 2026 Part D OOP cap: $2,000/year. Brand new.

6. What's new in 2026 (the $2,000 cap)

The single biggest Medicare change in decades. As of 2026, your annual out-of-pocket spending on covered Part D drugs is capped at $2,000. Doesn't matter if you're on $90,000/year Humira — once you hit $2,000 OOP, you pay $0 for any additional covered drugs the rest of the calendar year.

This is transformative for users of expensive specialty drugs (biologics for arthritis, oral chemotherapy, specialty cardiovascular drugs). It makes high-priced drugs effectively affordable for the first time in decades.

7. Which path is right for you?

Most people choose between two paths:

Path 1 — Original Medicare + Medigap + Part D. Predictable costs after deductible. Any Medicare-accepting doctor anywhere in the U.S. Best for snowbirds, complex conditions, frequent specialist users. Total monthly cost: ~$330–$450 (Part B + Medigap + Part D).

Path 2 — Medicare Advantage (Part C). Often $0 premium. Network restrictions. Annual OOP cap ($4–$8.8k). Includes extras like dental + vision + OTC card. Best for people in one geographic area with stable PCP relationship and budget focus.

8. The 5 most common Medicare mistakes

1. Missing the IEP and getting hit with the lifetime late-enrollment penalty. If you don't have creditable employer coverage at 65, sign up. The Part B penalty is 10% per year you delayed, FOR LIFE.
2. Picking Medicare Advantage without checking if your doctors are in-network. Networks can be narrow. We always check.
3. Not reviewing your plan at AEP. Carriers change formularies, networks, and benefits every year. Last year's best plan may not be this year's.
4. Buying Medigap after the 6-month OEP. You'll be medically underwritten. If you're in poor health, you may be denied.
5. Skipping Part D when you're on no medications. The late-enrollment penalty is permanent. Even a $0 premium plan keeps you protected.