Medicare Beneficiary Identifier | New Medicare Number, Who Dis?

Medicare Beneficiary Identifier

We’ve all been there. You’re playing with your new phone – customizing your settings, selecting your background photo, testing the camera quality – when a text comes in. From a number you don’t have saved. Maybe you ignore it or Google it or pretend that you know who they are. But most of us will inevitably send the “new phone, who dis?” text and endure the slightly awkward conversation that follows.

Medicare is doing the same thing. Kinda. 

They’re issuing new Medicare cards with new Medicare numbers (new Medicare numbers, new phone, get it?) They’ll begin mailing cards in April 2018, and all cards will be replaced by April 2019.

The new cards will not have Social Security Numbers (SSNs) on them and will no longer include the Health Insurance Claim Number (HICN) Instead, it will have the new Medicare numbers – known as Medicare Beneficiary Identifier (MBI) This change will help protect people with Medicare from identity theft and the illegal use of Medicare benefits.

Your client’s MBI will be randomly generated and contain 11 characters – both letters and numbers. Unlike HICNs, these numbers are “non-intelligent” and have no hidden meaning. Here is an example: 1EG4-TE5-MK73. These numbers are confidential, so make sure you treat them as such.

Each person with Medicare will receive their own MBI. Their spouses or dependents will also receive their own MBI.

There’s a few things you can do to be ready for this change.

Take a look at your systems and business processes. Are they ready to accept the Medicare Beneficiary Identifier? The MBI will be used for transactions such as billing, claim status, eligibility status, and other interactions with Medicare Administrative Contractor (MAC) contact centers by April 2018


There will be a transition period where Medicare will accept both MBI and HICN numbers, but your patients can start using their MBI as early as April 2018 and you need to be ready for it.


New cards will be mailed out starting in April 2018, and any new patients will receive an MBI not an HICN on their cards.

You can streamline this process by asking your clients to verify their addresses – they won’t receive a new card if their address is wrong. If the address you have on file is different from the address in electronic eligibility transaction responses from Medicare, encourage your clients to update their address in Medicare’s records. They have two options

  1. Call Social Security at 1-800-772-1213 or access their online account at ssa.gov/myaccount
  2. Call the Railroad Retirement Board (RRB) at 1-877-772-5772 *For patients who qualify for Medicaid under the RRB

The transition period

New cards will be mailed out in waves according to location starting in April 2018. Any clients new to Medicare will automatically receive one of the new cards. Local outreach, including outreach to health care providers, will occur before cards are due to arrive in a geographical area. This should limit clients’ vulnerability to scams.

From April 2018 to December 31, 2019, there will be an official transition period. During this time, you can use either the HICN or the MBI in your transactions. Place this number in the field where you would normally input the HICN. There is no need to specify which number you’re using – Medicare’s systems will be able to tell which one you’re using. You cannot submit both numbers on the same transaction.

During this time, crossover claims will operate the same way they do now. Medicare will process and transmit the claims using either the HICN or the MBI.

On January 1, 2020, the transition period will end. All transactions must use MBIs, even for dates of service prior to January 1, 2020. There are few exceptions:

  1. Appeals: Either the HICN or MBI can be used for claim appeals and related forms.
  2. Claim status query: Either HICNs or MBIs can be used to check the status of a claim (276 transactions) if the earliest date of service is before January 1, 2020. If the date of service is on or after January 1, 2020, then you must use the MBI.
  3. Span-date claims:
    1. You can use the HICN for 11X-Inpatient Hospital, 32X-Home Health, and 41X Religious Non-medical Health Care Institution claims if the ‘from date” is before the end of the transition period (December 31, 2019).
    2. You can submit claims received between April 1, 2018 and December 31, 2019 using the HICN or MBI.
    3. If a patient started 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 it is submitted after December 31, 2019.

Keeping your clients on track

When the mailing of the new Medicare cards begins in April 2018, you can start asking your clients if they have a new card with an MBI. Medicare will be sponsoring a large outreach program to help people with Medicare know that they need to bring their new cards with their MBI when they receive medical care.

You can also utilize the HIPAA Eligibility Transaction System (HETS) to check your client’s eligibility status with their HICN. The system will return a message that will say, “CMS mailed a Medicare card with a new Medicare beneficiary Identifier (MBI) to this beneficiary. Medicare providers, please get the new MBI from your patient and save it in your system(s).” in 271 Loop 2110C, Segment MSG. Check with your eligibility provider to see if they use HETS and how they plan to pass this information along to you.

Oops, I forgot my card

Since SSNs are being taken off of the new cards, they will no longer be needed for Medicare purposes and clients cannot provide them in lieu of their Medicare number. They need to use their MBI. If they forget their cards with their MBI, you can use your MAC’s secure portal to look them up. To look up their MBI, your client must tell you their first name, last name, date of birth, and SSN.

If you have clients that prefer not to give their SSN, they can retrieve their MBI by logging into www.mymedicare.gov. Clients with RRB benefits can ask for a replacement card through the RRB SMAC Beneficiary Contact Center at 1-800-833-4455, log into www.rrb.gov, or call the RRB office at 1-877-772-5772.

If you need help, you can visit the new Medicare Card Home and Provider webpages for updated information about the transition.

Take the time to understand what’s going to be happening over the next few months, and make sure your organization and your clients are prepared; you can be sure Medicare won’t be sending you any “new Medicare number, who dis?” messages.

Reports Don't Improve Outcomes

Topics: Industry Insights, Business Process