New Medicare Beneficiary Identifiers (MBI)

MBIs are required for all claims and transactions starting Jan. 1, 2020 (with few exceptions). Out with the old Health Insurance Claim Numbers (HICNs) and in with the new Medicare Beneficiary Identifiers (MBIs) as beneficiaries receive updated cards in advance of a Jan. 1, 2020, transition.

As of Aug. 19, the Centers for Medicare & Medicaid Services (CMS) had issued all-new Medicare cards, complete with MBIs, and encouraged providers to begin using the reconfigured, confidential identifiers for Medicare business, including claims submission and eligibility transactions. Although HICNs are still acceptable for use until the transition period ends, Dec. 31, 2019, MBIs are required for all claims and transactions starting Jan. 1, 2020 (with few exceptions), including those services provided prior to this date.

This will affect physicians, providers, and suppliers submitting claims to Medicare Administrative Contractors (MACs), including Durable Medical Equipment MACs (DME MACs) and Home Health and Hospice MACs, for services provided to Medicare beneficiaries. Use MBIs now for all Medicare transactions. The Centers for Medicare & Medicaid Services (CMS) finished mailing new Medicare cards. The new cards without Social Security Numbers (SSNs) offer better identity protection. Help protect your patients’ personal identities by getting their MBIs and using them for Medicare business, including claims submission and eligibility transactions.

The change comes several years after the Medicare Access and CHIP Reauthorization Act required CMS to remove beneficiaries’ Social Security Numbers (SSNs) from all Medicare cards in a move toward protecting personally identifiable information. The new randomly generated MBIs are noticeably different than HICNs, featuring an alphanumeric identifier, but are used in a similar manner.

Per CMS guidance, providers will enter MBIs in the same field where HICNs have typically gone (minus hyphens or spaces to avoid claim rejection) and will replace HICNs on Medicare transactions, including Billing, Eligibility Status, and Claim Status. The effective date of the MBI-like the old HICN-is the date each beneficiary was/is eligible for Medicare.

There are 3 ways you and your office staff can get MBIs:

  1. Ask your Medicare patients for their new Medicare cards when they come for care. If they didn’t get a new card, give them the Get Your New Medicare Card flyer in English or Spanish.
  2. You can look up MBIs for your Medicare patients when they don’t or can’t give them. Sign up for the Portal to use the tool. You can use this tool even after the end of the transition period – the tool doesn’t end on December 31, 2019. Even if your patients are in a Medicare Advantage Plan, you can look up their MBIs to bill for things like an indirect medical education. You must have your patient’s SSN for the search and it may differ from the HICN, which uses the SSN of the primary wage earner. If your Medicare patient doesn’t want to give the SSN, tell your patient to log into to get the MBI. If the lookup tool returns a last name matching error and the beneficiary’s last name includes a suffix, such as Jr. Sr. or III, try searching without and with the suffix as part of the last name.
  3. CMS will return the MBI on every remittance advice when you submit claims with valid and active HICNs through December 31, 2019. Get the MBI from the remittance advice and save it in your systems to use with your next Medicare transaction.

Should Medicare patients be unable to provide their MBI, providers can sign up for the portal and search based on patients’ SSNs. If patients are unwilling to provide their SSN, providers may suggest they visit to get their MBI. Alternatively, providers will find patients’ MBI on the remittance advice for claims with a valid and active HICN. Although MBIs take effect Jan. 1, 2020, Medicare notes several exceptions where HICNs will still be acceptable, including:

Medicare plan exceptions

  • Appeals — May use either HICNs or MBIs for appeals and related documents.
  • Adjustments — May use HICN indefinitely for some systems (Drug Data Processing, Risk Adjustment Processing, and Encounter Data) and for all records.
  • Reports — Must use HICN on incoming reports (quality reporting, etc.) and outgoing reports (Provider Statistical & Reimbursement Report, Accountable Care Organization reports, etc.) until further notice.

Fee-for-Service claim exceptions

  • Appeals — May use either HICNs or MBIs for claims, appeals, and related forms.
  • Audits — May use either HICNs or MBIs for audit purposes.
  • Claim status query — May use either HICNs or MBIs to check claim status if the earliest date of service on the claim is before Jan. 1, 2020. If you’re checking the status of a claim with a date of service on or after Jan. 1, 2020, you must use the MBI.
  • Span-date claims — May use HICNs for Inpatient Hospital, Home Health, and Religious Non-Medical Health Care Institution claims if the “From Date” is before the end of the transition period (Dec. 31, 2019). If a patient starts these services prior to Dec. 31, 2019, but stops those services after Dec. 31, 2019, you may submit a claim with either HICN or MBI.
  • Incoming premium payments — People with Medicare who don’t get SSA or RRB benefits and submit premium payments should use the MBI on incoming premium remittances. However, CMS will accept the HICN on incoming premium remittances after the transition period.


New Medicare Beneficiary Identifier (MBI) Get It, Use It