The Low-Down on Looking Up Medicare MBIs
By Ellen Terry


Now that Medicare has begun replacing patients’ Health Insurance Claim Numbers (HICN) with the Medicare Beneficiary Identifier (MBI), you might be wondering how you’ll find those MBIs.

Well, starting next month, look no further than the MBI Lookup Tool in Novitasphere, Novitas Solutions’ online portal. The look-up tool will return an MBI for a patient once that patient's the new Medicare card has been mailed.

Enrolling via the portal involves five steps; complete them now so you’ll be ready to use Novitasphere when the lookup tool is available. You also can use the portal to:

  • Submit claims, check their status, and make corrections;
  • Obtain beneficiary eligibility;
  • Retrieve and print remittance advices;
  • Submit medical review records;
  • Submit appeal requests with documentation;
  • Request immediate recoupments;
  • Submit general information requests; and
  • Obtain medical review claims details, such as status and letter copies. 

New Medicare enrollees are being assigned MBIs now, and current enrollees in Texas will receive new ID cards with an MBI this summer. The Railroad Retirement Board (RRB) will mail new Medicare cards to its beneficiaries June 1. You cannot tell from looking at MBIs of these patients that they are are eligible for Medicare because they are railroad retirees. CMS will return a message on the eligibility transaction response for every RRB patient MBI inquiry that will read, “Railroad Retirement Medicare Beneficiary.” The new RRB card will still have the RRB logo in the upper left corner and “Railroad Retirement Board” at the bottom.

The Centers for Medicare & Medicaid Services (CMS) recommends you use MBIs right away — as soon a patient has a card with the new ID. However, CMS has designated a transition period:

  • Through Dec. 21, 2019, you can file claims with either an MBI or an HICN. 
  • From October, 2018, to Dec. 31, 2019, CMS will return both numbers — the HICN and the MBI — on every remittance advice.
  • Starting Jan. 1, 2020, you must submit claims using MBIs (with a few exceptions).

See CMS' MLN Matters No. SE18006 for addtional information. Visit for more Medicare news and information.




Last Updated On

May 30, 2018

Related Content


Ellen Terry

Project Manager, Client Services

(512) 370-1391

Ellen Terry has been writing, editing, and managing communication projects at TMA since 2000. She hails from Victoria, Texas; has a journalism degree from Texas State University; and loves to read great fiction. Ellen and her husband have two grown sons and a couple of cats.

More stories by Ellen Terry