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Medicare Beneficiary Identifier (MBI)
The 11-character identifier unique to each Medicare enrollee, entered as the Enrollee ID without hyphens or dashes.
The MBI is the non-intelligent unique identifier that replaced the HICN on Medicare cards as a result of MACRA (2015). It contains uppercase alphabetic and numeric characters throughout its 11 characters and is unique to each Medicare enrollee. It must be submitted without hyphens or dashes.
Sources: ODAG protocol, Universe Table 1, Column C (Enrollee ID), PDF p. 17; CDAG protocol, Universe Table 1, Column C, p. 16; FA protocol, Enrollee ID field (Tables 1-4 Col A, Table 2IA Col A), PDF p. 10; SNPCC protocol, Universe Table 1 SNPE, Column ID C (PDF p. 9).