Medicare Claims Processing Manual (Pub. 100-04), Ch. 2 § 10.1.3
Importance of Medicare beneficiary identifiers
10.1.3 - Importance of Medicare beneficiary identifiers
(Rev. 4247, Issued: 03-01-19, Effective: 04-01-19, Implementation: 04-01 -19)
The term Medicare beneficiary identifier (Mbi) is a general term describing a
beneficiary's Medicare identification number. For purposes of this manual, Medicare
beneficiary identifier references both the Health Insurance Claim Number (HICN) and
the Medicare Beneficiary Identifier (MBI) during the new Medicare card transition
period and after for certain business areas that will continue to use the HICN as part of
their processes.
The Medicare beneficiary identifier is used in Medicare records to identify the
beneficiary. The provider or supplier obtains this number before billing. See §30 below
for a description of appropriate processes for obtaining the Medicare beneficiary
identifier.