New Medicare Card: Claim Reject Codes After January 1

Starting January 1, 2020, you must use Medicare Beneficiary Identifiers (MBIs) when billing Medicare regardless of the date of service. We will reject claims submitted with Health Insurance Claim Numbers (HICNs) with a few exceptions. We will reject all eligibility transactions submitted with HICNs.

If you do not use MBIs on claims after January 1, you will get:

  • Electronic claims reject codes: Claims Status Category Code of A7 (acknowledgment rejected for invalid information), a Claims Status Code of 164 (entity's contract/member number), and an Entity Code of IL (subscriber)
  • Paper claims notices: Claim Adjustment Reason Code (CARC) 16 "Claim/service lacks information or has submission/billing error(s)" and Remittance Advice Remark Code (RARC) N382 "Missing/incomplete/invalid patient identifier"

Do not wait. Protect your patients' identities by using MBIs now for all Medicare transactions. Need an MBI?

  • Ask your patients for their cards. If they did not get a new card, give them the Get Your New Medicare Card flyer in English or Spanish.
  • Use your Medicare Administrative Contractor's look-up tool. Sign up for the Portal to use the tool.
  • Check the remittance advice. We return the MBI on the remittance advice for every claim with a valid and active HICN.


  • CMS MLN Matters Article SE18006 Reissued: New Medicare Beneficiary Identifier (MBI) Get It, Use It
  • CMS MLN Connects dated October 24, 2019
  • CMS MBI provider webpage


            Last Updated Tue, 11 Feb 2020 09:29:05 +0000