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Health & drug plans


What do Medicare Beneficiary Identifiers (MBIs) mean for plans?

Medicare health and drug plans contracting or working with us should be using Medicare Beneficiary Identifiers (MBIs). 

You don’t need to change your members’ ID numbers unless those ID numbers include whole or parts of their Social Security Numbers. We urge you to keep using the unique identifiers that you’ve been using and not to include MBIs on your members’ ID cards.

Plans should keep exchanging data with us so we can make sure:

  • People in Medicare health and drug plans are making a smooth transition to using MBIs.
  • Eligible Retiree Drug Subsidy (RDS) sponsors are getting their subsidies.

How should plans be getting MBIs?

MARx will make a monthly crosswalk data file at the MAO/PDP Contract level. Every month during the transition period, MARx is sending out the file to help MAOs and Part D sponsors determine or match their beneficiaries’ Health Insurance Claim Numbers (HICNs) and MBIs.  

In March 2018, Plans got an “initial” (one-time only) HICN to MBI crosswalk file for past (back to 2006) and present membership. Now, a monthly file is sent to Plans with any new enrollment changes.

During and after the transition period, MARx is only showing the MBI on files and reports. The MARx UI is showing both the HICN and the MBI during the transition, but only the MBI when the transition’s over.

If you send a HICN after the transition period's over, we won’t send you a new transaction reply code. MARx will send you the same transaction code that that’s sent now (008) when a health insurance claim number can’t be found.  

How should plans be using MBIs?

Even though we’ve moved to MBIs for claims and other Medicare business, this change didn't affect how you use Social Security numbers (SSNs) to identify and verify your members.

Crossover claims

Through Medicare's Coordination of Benefits Agreement (COBA) crossover process, we shared a crosswalk with COBA trading partners (supplemental insurers, Medicaid, etc.) that’ll show them their covered members' and benefit recipients' HICNs and the MBIs that go with them. So, if COBA trading partners use HICNs for crossover claims processing, they’ll also have access to MBIs so they’ll be ready for the Medicare crossover claims that started in April 2018. For crossover claims processing, during and even after the transition period, we’ll keep sending you plan membership IDs or state Medicaid recipient IDs like we've always done.

We're not adding beneficiaries who’ve cancelled their plan enrollment and have never existed in the plan to the MARx Crosswalk File. We’re only adding those beneficiaries who are now enrolled or were enrolled in a plan to the MARx Crosswalk File.

Using the card image

You can keep using the Medicare card image in your plan materials, and in digital formats like video, on the web, or however you need to for business purposes. Here's a high resolution image of the card or you can use a generic card image you've made in videos or in other online or electronic materials. We're not providing a generic image for use. 

You don’t have to resubmit marketing materials that have already been approved or accepted if the only change you've made is to update the Medicare card image.

You can't alter the Medicare card image in any way, but you can use a black and white version of the image for print materials.

How do plans protect MBIs?

Like SSNs and Health Insurance Claim Numbers (HICNs), MBIs are confidential and should be protected as Personally Identifiable Information. Here’s how plans should be protecting the integrity of MBIs:

Don’t give MBIs over the phone

Plan call centers didn't give HICNs to beneficiaries over the phone and plan call centers also shouldn’t give MBIs to a beneficiaries over the phone.  Beneficiaries can usually get most of their health plan services with their plan IDs, so they shouldn’t need their MBIs.

Plans should always confirm they have the right address on file for beneficiaries and tell them to make sure that the Social Security Administration has their correct mailing address.

If beneficiaries call to ask for their MBIs because they haven’t gotten theirs yet, plans should let them know that they should contact Medicare.

Use MBIs on standardized materials

The HICN was used on many standardized forms and letters. We’ve been revising these materials just for MBI use, but until they're ready, plans should keeping using the forms they have with either the HICN or MBI as appropriate.

Share MBIs with downstream partners

Plans can share MBIs with downstream partners for Medicare-related business (payments, treatment and healthcare operations) like they share HICNs today. Plans should make sure MBIs are secure and use the HIPAA “Minimum Necessary” guidelines.

Keep HICN/MBI crosswalk records

Plans should keep records as required by existing federal and state regulations.

Where can plans get more information about MBIs?

To learn more, you can:

Plans will get keep getting information about MBIs the same way we usually send them information about other topics, such as the Health Plan Management System (HPMS), the RDS Program website, RDS program correspondence, Medicare Advantage Prescription Drug (MAPD) Release Letters, and updates to the Plan Communications Users Guide.

You can also check back here on our webpage or email us your technical questions to the right email box below:

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