What Is MAC (Medicare Administrative Contractor)?
A Medicare Administrative Contractor is a private organization that contracts with CMS to process Medicare Part A and Part B claims (or DME claims) within a defined geographic jurisdiction, applying CMS coverage rules and publishing local coverage determinations.
- Identify your A/B MAC and DME MAC by jurisdiction, monitor the MAC's website for LCD updates and provider bulletins, and use the MAC's portal for claim status, redeterminations, and overpayment recoupment management.
MAC (Medicare Administrative Contractor)
Also known as: Medicare Administrative Contractor; Part A/B MAC; DME MAC
A Medicare Administrative Contractor is a private organization that contracts with CMS to process Medicare Part A and Part B claims (or DME claims) within a defined geographic jurisdiction, applying CMS coverage rules and publishing local coverage determinations.
Definition
CMS divides the United States into 12 A/B MAC jurisdictions and 4 DME MAC jurisdictions. A/B MACs include Noridian Healthcare Solutions (Jurisdictions E and F covering the West), Novitas Solutions (Jurisdictions H and L covering parts of the South and Northeast), Palmetto GBA (Jurisdictions J and M), CGS Administrators, First Coast Service Options (Jurisdiction N — Florida), National Government Services, and WPS. MACs process and adjudicate claims, conduct medical review, publish Local Coverage Determinations (LCDs), handle provider enrollment via PECOS, conduct provider education, and process redeterminations (the first level of Medicare appeal).
Example
A Florida physician submits a Medicare Part B claim — it routes to First Coast Service Options (Jurisdiction N MAC) for adjudication. If denied, the redetermination request goes to First Coast within 120 days. The same patient seen in California would have the claim processed by Noridian (Jurisdiction E).
Common Misconceptions
MACs are not CMS — they are private contractors. MAC contracts rotate every 5-7 years, so the MAC processing your jurisdiction's claims may change. Each MAC publishes its own LCDs; a service covered in one MAC jurisdiction may have different documentation requirements in another.
Practical Application
Identify your A/B MAC and DME MAC by jurisdiction, monitor the MAC's website for LCD updates and provider bulletins, and use the MAC's portal for claim status, redeterminations, and overpayment recoupment management.
Related Terms
CMS
CMS is the federal agency within the U.S. Department of Health and Human Services that administers Medicare, jointly administers Medicaid and CHIP with the states, and oversees the Health Insurance Marketplaces and HIPAA administrative simplification.
Read definition arrow_forwardMedicare Part A/B/C/D
Medicare is divided into four parts: Part A covers hospital inpatient, SNF, hospice, and home health; Part B covers physician services and outpatient care; Part C (Medicare Advantage) is private plans replacing A and B; Part D covers prescription drugs.
Read definition arrow_forwardLCD / NCD (Local & National Coverage Determinations)
An NCD is a nationwide CMS coverage policy specifying whether Medicare will cover a service; an LCD is a coverage policy issued by a Medicare Administrative Contractor (MAC) for its jurisdiction when no NCD applies, defining medical necessity criteria and covered diagnosis codes.
Read definition arrow_forwardWhere This Applies on MedPrecision
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