Medicare Beneficiary Identifiers (MBIs)

Starting January 1, 2020, you MUST submit claims using MBIs (with a few exceptions), no matter what date you performed the service. We’re now in a transition period that goes through December 31, 2019, where you can use either the HICN or the MBI to exchange data with us. 

• Claim status query – You can use either the HICN or the MBI to check the status of a claim (276 transactions) if the earliest date of service on the claim is before January 1, 2020. If you’re checking the status of a claim with a date of service on or after January 1, 2020, you have to use the MBI.
• Span-date claims – You can use the HICN for 11X-Inpatient Hospital, 32X-Home Health (home health claims & Request for Anticipated Payments (RAPs)), and 41X-Religious Non-Medical Health Care Institution claims if the “From Date” is before the end of the transition period (12/31/2019). You can submit claims received between April 1, 2018 and December 31, 2019 using either the HICN or the MBI.  If a patient starts getting services in an inpatient hospital, home health, or religious non-medical health care institution before December 31, 2019, but stops getting those services after December 31, 2019, you may submit a claim using either the HICN or the MBI, even if you submit it after December 31, 2019.

Source: https://www.cms.gov/Medicare/New-Medicare-Card/index