If you aren’t eligible for premium-free Medicare Part A, then you can sign up for Medicare Part B even if you don’t have Medicare Part A.
To qualify you must be 65 or older, a resident of the US, and either a US citizen or an immigrant lawfully admitted for permanent residence who has lived in the U.S. without a break for the 5-year period immediately before the month you file for enrollment in Part B.
- Enrolling Medicare Part A & Part B [pdf]. Medicare.Gov.
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