Plus: Use zeroes to become an MBI hero. Now that all existing Medicare beneficiaries have received their Medicare Beneficiary Identifier numbers, it’s smooth sailing, right? Wrong. Reminder: Although the Centers for Medicare & Medicaid Services has finished replacing old Health Insurance Claim Numbers with MBIs for all existing beneficiaries, Medicare claims systems will take HICN numbers or MBI numbers until Dec. 31. The transition period seems to be giving rise to a problem described by HHH Medicare Administrative Contractor CGS. “In some situations where providers are submitting claims under the Medicare Beneficiary Identifier (MBI), the claim processes under the beneficiary’s Health Insurance Claim Number (HICN). This seems to occur when the Common Working File (CWF) shows that a new HICN is assigned to the beneficiary,” CGS says on its claims processing problems webpage. “New and subsequent claims are processing under the new HICN; when the prior claim information is under the old HICN and is not cross referencing to the new HICN,” CGS continues. “This is causing claims to go to the return to provider (RTP) file with reason code 38107 (matching home health RAP cannot be found) and 37402 (hospice sequential billing).” The issue has been reported to the system maintainer, the MAC says. Use This Tip To Avoid A Trap Don’t forget that the new MBIs do not contain “Os,” but instead utilize zeros, CMS reminds providers in a new message. Nuts and bolts: Each unique MBI consists of 11 randomly-generated alphanumeric characters. CMS uses the numbers 0-9 and uppercase letters from A-Z in the MBIs, according to MLN Matters SE18006. Important: An exception to this rule is that the letters S, L, O, I, B, and Z are not included. CMS excluded these letters to avoid confusion. Note: The MLN Matters article is at www.cms.gov/Outreach-and-Education/Medicare-Learning-Network-MLN/MLNMattersArticles/downloads/SE18006.pdf.