Medicare Beneficiary Identifier (MBI)
Medicare Glossary
The unique 11-character number on your Medicare card that identifies you for Medicare services. The MBI replaced the old Health Insurance Claim Number (HICN) that was based on Social Security numbers.
This content is for educational purposes only and does not constitute a recommendation of any specific Medicare plan. Benefits, costs, and availability vary by plan and location. For complete information about your Medicare options, visit Medicare.gov or call 1-800-MEDICARE (1-800-633-4227), TTY: 1-877-486-2048, available 24 hours a day, 7 days a week.
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