Medicare Part B.

In plain English

Medicare Part B is the medical-insurance part of Medicare. It covers things that happen outside a hospital stay: doctor appointments, lab tests, outpatient surgery, durable medical equipment like a walker, and most preventive screenings. You pay a monthly premium for Part B, plus a yearly deductible, and after that you usually pay 20 percent of the cost for many services while Medicare pays the rest. Part B is the companion to Part A, which covers hospital stays.

01Why it matters

If you skip Part B when you first become eligible and do not have other qualifying coverage, you can face a lifetime late-enrollment penalty added to your premium for as long as you have it. That penalty is permanent, so the timing of your decision follows you for decades.

02The math, step by step

Say you see your doctor for a knee problem and the visit plus an X-ray costs $300. After you have met your yearly Part B deductible, Medicare pays 80 percent and you pay the remaining 20 percent, which is $60. For 2026, the standard Part B premium is $202.90 a month and the annual deductible is $283 (higher earners pay an income-based surcharge).

03What this is NOT

04Receipts

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