If you are a Medicare beneficiary in Georgia and you've been on Medicare longer than the spring of 2018, you remember the day you opened the mailbox and found a new Medicare card. The card looked different. The familiar number printed on the front, your Health Insurance Claim Number (HICN), which was based on your Social Security Number, was gone. In its place was a new, randomly-generated 11-character identifier called the Medicare Beneficiary Identifier (MBI).

That change was not cosmetic. It was the largest beneficiary identifier transition in Medicare's history, mandated by Congress, executed across hundreds of millions of records, and accompanied by a complete overhaul of provider billing systems, MAC claims processing infrastructure, Medicare Advantage and Part D plan operations, and beneficiary documentation. The change was authorized by Section 501 of the Medicare Access and CHIP Reauthorization Act of 2015 (MACRA).

The reason was straightforward. For more than 50 years from Medicare's enactment in 1965, every beneficiary's Medicare card prominently displayed their Social Security Number as the basis of the HICN. The HICN was on every claim, every coverage document, every Medigap policy, every provider record, every Medicare Summary Notice. After major healthcare data breaches in the mid-2010s, including the Anthem and OPM breaches, the security implications of routinely exposing SSNs in healthcare records had become indefensible. MACRA Section 501 required CMS to remove SSNs from Medicare cards and to assign every beneficiary a new MBI.

CMS executed the transition between April 2018 and April 2019. During a transition period from April 1, 2018 through December 31, 2019, both HICN and MBI were accepted in claims, eligibility queries, and other Medicare transactions. Beginning January 1, 2020, MBI-only requirements took effect. Today, every Georgia Medicare beneficiary's identifier in every Medicare transaction is the MBI.

This guide explains the MACRA statutory mandate, the MBI structure, the transition timeline, the new card design, the provider system conversion, how Palmetto GBA (the Part A/B MAC for Alabama, Georgia, and Tennessee) and CGS Administrators (the DME MAC for Georgia) implemented the change, how to request a replacement card if yours was lost or never received, how the MBI interacts with Medicare Advantage and Part D plan-issued cards, how Railroad Retirement Beneficiaries (RRB) fit in, the identity theft reduction rationale, common compliance and beneficiary issues, and how this transition continues to affect every Medicare transaction in Georgia today.

The transition is complete. The MBI is in operation. The HICN is retired. The question for Georgia beneficiaries today is operational, covering how to get a replacement card, how to recognize scam calls asking for "Medicare number verification," how to coordinate the MBI with Medicaid for dual eligibles, and how to ensure providers have the correct MBI on file.

The statutory mandate

MACRA 2015

  • Medicare Access and CHIP Reauthorization Act of 2015 (MACRA)
  • Signed in 2015 by President Obama
  • Repealed the Sustainable Growth Rate (SGR) physician payment formula
  • Established the Quality Payment Program (MIPS and Advanced APMs)
  • Among many other provisions, included Section 501 mandating SSN removal from Medicare cards

Section 501: What It Required

  1. Removal of SSNs from Medicare cards within 4 years of enactment
  2. Replacement identifier that does not include SSN, BIC, or any embedded SSN
  3. Distribution of new cards to all Medicare beneficiaries
  4. Update of all CMS, MAC, MA plan, and Part D plan systems
  5. Coordination with SSA, RRB, and other relevant agencies
  6. Beneficiary education

Why MACRA Acted

  • Anthem data breach (2015): tens of millions of records compromised, including SSNs
  • OPM data breach (2014-2015): tens of millions of records compromised
  • Numerous smaller healthcare breaches
  • GAO and OIG reports documenting SSN exposure risk
  • Bipartisan beneficiary advocacy organization concern (AARP, Medicare Rights Center, others)

The HICN: What Was Being Replaced

Structure

  • Social Security Number (typically the wage earner's)
  • Followed by one- or two-character BIC suffix
  • Examples:
    • 123-45-6789-A: primary wage earner
    • 123-45-6789-B: spouse of wage earner
    • 123-45-6789-D: widow(er)
    • 123-45-6789-T: uninsured (Part A entitlement based on transitional or non-contributory status)
    • 123-45-6789-M: Part B only without Part A
  • Multiple BIC codes existed for various entitlement categories

Problems

  • SSN exposed on every Medicare card
  • SSN exposed on every claim
  • SSN exposed in provider records
  • Spouses and widows had the wage earner's SSN with a different suffix, meaning multiple people were associated with one SSN
  • Identity theft risk
  • Difficult to remediate after a breach (one cannot change one's SSN)

The MBI: What Replaced It

Structure

  • 11 alphanumeric characters
  • Specific position rules govern which character types appear at each position
  • Certain letters are excluded from the character set to prevent confusion with similar-looking digits
  • No embedded meaning; does not encode SSN, date of birth, or any beneficiary characteristic

Key properties

  • Randomly generated by SSA
  • No embedded meaning, does not encode SSN, DOB, age, sex, or any beneficiary characteristic
  • Unique to each beneficiary: spouses, widows, and disabled adult children each get their own MBI (no shared identifier as with HICN)
  • Stable: does not change with MA enrollment, state moves, or status changes (with limited exceptions)

Generation and distribution

  • SSA generates MBIs for Medicare beneficiaries
  • CMS coordinates distribution of new cards
  • New cards mailed in geographic waves April 2018 through April 2019
  • Beneficiaries received cards at their address of record

Transition timeline

April 2018

  • Mass mailing of new cards began
  • Mailing proceeded in geographic waves across the country
  • New enrollees beginning April 2018 received MBI cards directly

April 1, 2018 through December 31, 2019 (transition period)

  • HICN and MBI both accepted in claims
  • Eligibility queries returned MBI
  • Provider lookup tools available
  • Beneficiary education campaign underway

Through April 2019

  • All Medicare beneficiaries scheduled to receive new cards

January 1, 2020 to present

  • MBI-only for Medicare transactions
  • HICN no longer accepted in claims (with limited exceptions)
  • All eligibility queries return MBI

The new Medicare card design

  • Red, white, and blue color scheme retained for recognizability
  • MBI displayed prominently (replacing HICN)
  • "Medicare Beneficiary Identifier" label
  • Effective dates for Part A and Part B
  • No SSN anywhere on card
  • Paper card (not plastic), same material as historical card

Provider compliance

System conversion

  • Provider billing systems updated to accept MBI
  • Practice management systems (PMS), electronic health records (EHR), clearinghouses, and payers all updated
  • Transition support from MACs, vendors, and professional associations

Eligibility verification

  • Providers verify MBI through:
    • Medicare card (beneficiary brings to appointment)
    • HIPAA Eligibility Transaction System (HETS) query
    • MAC provider portal (Palmetto GBA, CGS Administrators)
    • MBI Lookup Tool (CMS-provided during transition)

Documentation

  • MBI on all claims
  • MBI in EHR
  • MBI in coverage documents
  • MBI in beneficiary correspondence

MAC implementation in Georgia

Palmetto GBA (Part A/B MAC for Alabama, Georgia, and Tennessee)

  • Updated all claims processing systems
  • Provided provider education throughout transition
  • Offered MBI lookup tools
  • Coordinated with Georgia health systems

CGS Administrators (DME MAC for Georgia)

  • Updated DMEPOS claims processing systems
  • Coordinated with DMEPOS suppliers including major Atlanta CBA suppliers
  • Provided supplier education

Coordination with Georgia Medicaid

  • Georgia Department of Community Health (DCH) administers Medicaid
  • Dual eligibles have both Medicare MBI and Georgia Medicaid ID
  • Both identifiers used in dual coverage scenarios

Railroad Retirement Beneficiaries (RRB)

  • Some Medicare beneficiaries receive benefits through the Railroad Retirement Board rather than SSA
  • RRB beneficiaries also have MBIs
  • New cards distributed through coordination between SSA, CMS, and RRB
  • Replacement cards for RRB beneficiaries: contact the Railroad Retirement Board directly at rrb.gov

Medicare Advantage and Part D coordination

  • MA plans (including Aetna, Humana, UnitedHealthcare, Kaiser, WellCare, others operating in Georgia) issue plan-specific cards with plan ID
  • MA card and Medicare card with MBI; beneficiaries may carry both
  • Part D plans issue plan-specific cards
  • MBI is the underlying CMS identifier; plan IDs are for plan-specific operations

Identity theft and Medicare scams

Why this matters

  • Medicare scams remain common
  • Scammers may ask for "Medicare number verification"
  • The MBI is treated as sensitive; beneficiaries should not share it casually
  • However, the MBI is needed for legitimate healthcare encounters

Red flags

  • Unsolicited calls asking for Medicare number
  • Pressure to "verify" Medicare information
  • Offers of free medical equipment or "Medicare benefits"
  • Threats of Medicare termination
  • Requests for SSN or financial information

Legitimate uses

  • Healthcare provider eligibility check
  • Pharmacy at point of service
  • Medicare provider portal authenticated access
  • Medicare appeals correspondence

Reporting Medicare fraud

  • 1-800-MEDICARE
  • HHS OIG Hotline 1-800-HHS-TIPS (1-800-447-8477)
  • Senior Medicare Patrol (SMP), in Georgia via GeorgiaCares

Replacement card process

Through Medicare.gov

  1. Log into MyMedicare.gov
  2. Request replacement card
  3. Card mailed to address on file

Through 1-800-MEDICARE

  • Call 1-800-633-4227
  • Identity verification
  • Request replacement

Through Social Security Administration

  • Visit local SSA office
  • Online request through ssa.gov
  • Phone: 1-800-772-1213

For RRB beneficiaries

  • Contact the Railroad Retirement Board through rrb.gov

Timing

  • Generally 30 days for delivery
  • Update address with SSA if address has changed

Worked examples

Example 1: Fulton County, Age 70, New Card Receipt 2018

Patient: 70-year-old Fulton County resident, on Medicare since 2017. Experience: Received new Medicare card with MBI in May 2018 during Georgia's wave of mailings. Old HICN card retired. Provider visits: During transition period (April 2018 through December 2019), Emory practice accepted either HICN or MBI. After January 1, 2020, only MBI accepted. Outcome: Smooth transition; new card stored securely; MBI on file with all providers.

Example 2: DeKalb County, Age 75, Lost Card Replacement

Patient: 75-year-old DeKalb County resident, misplaced Medicare card in 2025. Process: Logged into MyMedicare.gov, requested replacement card; received new card within approximately 3 weeks at home address. Cost: Free; replacement cards are not charged to beneficiary. Alternative: Could have called 1-800-MEDICARE or visited SSA office.

Example 3: Cobb County, Age 68, Dual Eligible Coordination

Patient: 68-year-old Cobb County resident, dual eligible (Medicare + Georgia Medicaid). Identifiers:

  • Medicare MBI on Medicare card
  • Georgia Medicaid Member ID on Medicaid card
  • Both used: providers verify both for proper billing coordination

Coordination: Medicare pays primary; Medicaid pays secondary or covers Medicare cost-sharing under QMB or other Medicare Savings Program.

Example 4: Worth County, Age 72, Rural Beneficiary

Patient: 72-year-old Worth County (rural southwest Georgia) resident. Experience: Received new Medicare card with MBI in summer 2018; mailing reached rural address timely. Initial confusion about whether card was legitimate was resolved through GeorgiaCares SHIP and 1-800-MEDICARE. Local providers: Phoebe Putney and local independent providers all updated systems and accepted MBI.

Example 5: Bibb County, Age 80, ESRD Beneficiary MBI

Patient: 80-year-old Bibb County resident, on Medicare based on End-Stage Renal Disease (ESRD). MBI: Same MBI structure as all Medicare beneficiaries. ESRD status does not affect MBI format or generation. Use: Dialysis center, nephrology practice, transplant center (if applicable) all use MBI for billing.

Example 6: Hall County, Age 67, Railroad Retirement Beneficiary

Patient: 67-year-old Hall County resident, retired railroad worker receiving benefits through RRB rather than SSA. MBI: Received MBI through RRB-CMS coordination. Same 11-character structure. Replacement: Contacts Railroad Retirement Board through rrb.gov for replacement card, distinct from SSA process.

Best practices for Georgia providers

  1. Verify MBI at every visit through MAC portal or HETS query
  2. Store MBI securely in EHR and practice management systems
  3. Train front office staff on MBI handling and scam awareness
  4. Educate beneficiaries to bring Medicare card to appointments
  5. Reconcile MBI changes when CMS issues a new MBI (rare but possible)
  6. Maintain HIPAA compliance in MBI storage and transmission
  7. Reference Palmetto GBA and CGS guidance on MBI use
  8. Verify MA plan ID separately from MBI for MA beneficiaries
  9. Support beneficiaries asking about replacement cards by referring to 1-800-MEDICARE or SSA
  10. Coordinate with Medicaid for dual eligibles
  11. Maintain accurate beneficiary contact information for card delivery
  12. Reference CMS New Medicare Card resources for current guidance
  13. Audit systems periodically for HICN remnants
  14. Educate clinical staff on Medicare scam awareness so they can warn beneficiaries

Common issues

  1. Beneficiary still has old HICN card: needs replacement
  2. Beneficiary never received new card: request replacement
  3. Lost or stolen card: request replacement; report theft if suspected
  4. Provider system not updated: possible during early transition; resolved by 2020
  5. MBI mistyped in claims: transcription errors possible due to character set
  6. Scam calls: beneficiaries pressured to "verify" Medicare number
  7. MA plan card confusion: beneficiary unsure which card to present
  8. Part D plan card confusion: beneficiary unsure which card to present
  9. Replacement card delivery delay: usually approximately 30 days
  10. Dual eligible coordination: both Medicare MBI and Medicaid ID needed
  11. RRB beneficiary process: different from SSA process
  12. MBI updates: rare but possible if compromise suspected
  13. Documentation gaps: old records may still contain HICN
  14. Beneficiary memory: older beneficiaries may remember HICN format and be confused by new format

Frequently Asked Questions

The Medicare Beneficiary Identifier is an 11-character alphanumeric identifier that replaced the SSN-based Health Insurance Claim Number (HICN) on Medicare cards. It has no embedded meaning and does not encode any personal information such as your Social Security Number, date of birth, or other characteristics.

Section 501 of MACRA 2015 mandated SSN removal from Medicare cards to reduce identity theft risk. After major healthcare data breaches in the mid-2010s that exposed millions of Social Security Numbers stored in healthcare systems, Congress required CMS to transition to a new identifier that no longer exposed beneficiary SSNs in routine healthcare transactions.

Request a replacement through Medicare.gov (log into MyMedicare.gov), by calling 1-800-MEDICARE (1-800-633-4227), or by visiting your local Social Security Administration office. Replacement cards are free. Railroad Retirement Board beneficiaries should contact the RRB directly through rrb.gov.

Only share your MBI with legitimate healthcare providers, plans, and Medicare contractors. Never share it with unsolicited callers. Medicare scams asking for "Medicare number verification" are common. If you receive a suspicious call, hang up and call 1-800-MEDICARE directly to verify.

No. The MBI is stable across Medicare Advantage enrollment, state moves, and most status changes. Your Medicare Advantage plan will issue a separate plan-specific ID card, but your underlying MBI remains the same.

Get help with Medicare card and MBI issues in Georgia

  • Medicare: 1-800-MEDICARE (1-800-633-4227); medicare.gov
  • MyMedicare.gov: online account for card replacement
  • Social Security Administration: 1-800-772-1213; ssa.gov
  • Railroad Retirement Board (RRB): rrb.gov
  • Palmetto GBA (Part A/B MAC for GA): palmettogba.com
  • CGS Administrators (DME MAC for GA): cgsmedicare.com
  • GeorgiaCares SHIP: georgiacares.org
  • Medicare Rights Center: 1-800-333-4114; medicarerights.org
  • HHS OIG Hotline (fraud): 1-800-HHS-TIPS (1-800-447-8477)
  • Senior Medicare Patrol (SMP) Georgia: via GeorgiaCares
  • Atlanta Legal Aid: 404-377-0701; atlantalegalaid.org
  • Georgia Legal Services Program: 1-800-498-9469; glsp.org
  • 211 Georgia: dial 211
  • Eldercare Locator: 1-800-677-1116; eldercare.acl.gov
  • Identity Theft Resource Center: idtheftcenter.org
  • Federal Trade Commission identity theft: identitytheft.gov

Find personalized help navigating Medicare card and MBI questions in Georgia at brevy.com.

This guide is provided for educational purposes by Brevy. It does not constitute legal advice. Medicare card and MBI processes are administered by CMS, SSA, and RRB. Consult Medicare, SSA, RRB, GeorgiaCares SHIP, or qualified legal counsel for case-specific guidance. Last verified: 2026-05-14.

BC

Brevy Care Team

Expert eldercare guidance from Brevy's team of healthcare professionals and researchers.