What Is a Medicare Administrative Contractor (MAC)?
A Medicare Administrative Contractor (MAC) is a private health insurer contracted by the Centers for Medicare & Medicaid Services (CMS) to process Medicare claims for specific geographic regions. MACs handle Part A and Part B claims, provide customer service to healthcare providers, and ensure compliance with Medicare policies.
The Centers for Medicare & Medicaid Services contracts with 12 regional MACs across the United States. These contractors replaced the previous fiscal intermediaries and carriers system in 2003 to streamline Medicare administration and improve efficiency.
What Are the Primary Functions of Medicare Administrative Contractors?
MACs perform 8 essential functions for the Medicare program. These functions include processing claims, conducting audits, providing education, managing appeals, detecting fraud, maintaining provider enrollment, offering customer service, and ensuring policy compliance.
Claims Processing and Payment
MACs process Medicare Part A and Part B claims submitted by healthcare providers. The contractors review claims for accuracy, verify patient eligibility, calculate reimbursement amounts, and issue payments within regulatory timeframes. According to CMS data, MACs process over 1.2 billion Medicare claims annually with an accuracy rate exceeding 95%.
Provider Education and Outreach
MACs deliver training programs to healthcare providers on Medicare billing requirements. These programs cover proper coding procedures, documentation standards, compliance guidelines, and recent policy updates. MACs conduct webinars, publish newsletters, and maintain online resources to support provider education.
Medical Review and Audit Activities
MACs conduct medical reviews to ensure services meet Medicare coverage criteria. The contractors perform prepayment reviews, postpayment audits, and targeted probe reviews based on billing patterns. Studies by the Office of Inspector General show that MAC audits prevent approximately $3.8 billion in improper payments annually.
Appeals and Redetermination Processing
MACs handle first-level appeals when providers dispute claim denials. Healthcare providers can request redetermination within 120 days of receiving an initial determination. MACs must issue redetermination decisions within 60 days for Part A claims and 30 days for Part B claims.
How Many Medicare Administrative Contractors Operate in the United States?
MACs are multi-state, regional contractors responsible for administering both Medicare Part A and Medicare Part B claims. CMS divides the country into Jurisdiction A through Jurisdiction N, with each MAC serving multiple states. The jurisdiction system ensures regional coverage and allows MACs to develop expertise in local healthcare markets.
MAC Jurisdictions and Coverage Areas
Each MAC jurisdiction covers 3 to 8 states or territories. Jurisdiction
- A includes Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont.
- Jurisdiction B covers Delaware, the District of Columbia, Maryland, New Jersey, and Pennsylvania.
- The remaining jurisdictions span the central, southern, and western regions.
What Is the Difference Between DME MACs and A/B MACs?
The Centers for Medicare & Medicaid Services contracts with 4 DME MACs that operate across separate jurisdictions from the 12 A/B MACs.
| Feature | DME MACs | A/B MACs |
| Number of Contractors | 4 | 12 |
| Primary Function | Process medical equipment and supplies claims | Process institutional and professional service claims |
| Claims Processed | Wheelchairs, oxygen equipment, hospital beds, prosthetics, orthotics, parenteral nutrition | Hospital services, skilled nursing facility services, physician services, and outpatient facility services |
| Provider Types Served | Durable medical equipment suppliers, prosthetic and orthotic suppliers | Hospitals, skilled nursing facilities, physicians, and outpatient facilities |
| Jurisdiction Coverage | Separate DME jurisdictions | Geographic jurisdictions A through N |
| Specialization | Equipment coverage policies and supplier standards | Clinical service requirements and facility regulations |
How Do Healthcare Providers Contact Their Medicare Administrative Contractor?
Healthcare providers contact their MAC through dedicated phone lines, online portals, or written correspondence. Each MAC maintains a provider contact center with toll-free numbers for billing inquiries, claim status checks, and policy questions. The contact center operates during standard business hours with extended availability during peak periods.
Online Portal Access and Resources
MACs offer secure online portals where providers can submit claims electronically, check claim status, download remittance advice, and access policy documents. Providers must register for portal access and maintain proper credentials.
What Are Provider Enrollment Requirements With MACs?
Healthcare providers must enroll with their MAC before submitting Medicare claims. The enrollment process requires
- Completing the CMS-855 application
- Submitting supporting documentation
- Undergoing background checks
- Paying enrollment fees
MACs review applications within 60 to 90 days and issue provider transaction access numbers (PTAN) upon approval.
Enrollment categories include individual practitioners, group practices, institutional providers, and suppliers. Each category has specific documentation requirements. Physicians must submit medical licenses, DEA certificates, and board certifications. Facilities must provide accreditation certificates, state licenses, and ownership disclosure statements.
How Do MACs Handle Medicare Coverage Determinations?
MACs issue local coverage determinations (LCDs) that specify when Medicare covers specific services in their jurisdiction. These determinations provide detailed coverage criteria, coding guidelines, and documentation requirements for medical services.
National Coverage Determinations Versus Local Coverage Determinations
National coverage determinations (NCDs) apply uniformly across all jurisdictions, while LCDs vary by MAC region. CMS issues NCDs for services requiring nationwide policy consistency. MACs develop LCDs for services without national policies based on regional medical practices and evidence. Providers must follow both NCDs and their MACs’ LCDs when billing Medicare.
What Is the MAC Medical Review Process?
The MAC medical review process evaluates whether services meet Medicare coverage, coding, and payment requirements.
- MACs conduct prepayment reviews before paying claims and postpayment reviews after payment.
- MACs use automated edits, manual reviews, and complex medical reviews depending on claim characteristics.
- Automated edits check for basic errors like invalid codes or missing information.
- Manual reviews assess medical necessity and documentation adequacy.
- Complex medical reviews involve clinical staff evaluating the appropriateness of treatment.
How Do Providers Appeal MAC Claim Denials?
Providers appeal MAC claim denials through a five-level Medicare appeals process. Level one involves requesting redetermination from the MAC within 120 days of the initial determination. Level two allows reconsideration by a Qualified Independent Contractor. Level three provides administrative law judge hearings for disputes exceeding monetary thresholds.
The MAC must issue redetermination decisions within specific timeframes. Part A claims require decisions within 60 days. Part B claims require decisions within 30 days. Studies published in Health Affairs show that providers win approximately 45% of MAC redeterminations through improved documentation or policy clarification.
Conclusion
Managing MAC requirements requires expertise in billing rules, documentation, and coverage policy changes. Wisconsin Medical Billing provides comprehensive MAC management services that ensure clean claims submission and maximum compensation for your practice.
Contact us today to streamline your Medicare billing operations and improve your revenue cycle performance.
FAQs
What Are the MAC Audit and Recovery Activities?
MACs conduct audits to identify improper payments and recover overpayments. The contractors perform targeted probe reviews, comprehensive medical reviews, and prepayment reviews based on billing patterns.
What Technology Systems Do MACs Use for Claims Processing?
MACs use advanced claims-processing systems that incorporate artificial intelligence, automated edits, and fraud-detection algorithms.
How Do MACs Support Provider Customer Service?
MACs provide customer service through multiple channels, including phone support, email inquiries, online chat, webinars, and in-person education sessions.
What Are the MAC Performance Standards and Metrics?
CMS evaluates MAC performance using 23 specific metrics across claims processing, customer service, appeals, and provider education.
How Often Does CMS Rebid MAC Contracts?
CMS rebids MAC contracts approximately every 10 years through competitive procurement processes. The rebidding allows CMS to incorporate new requirements and update technology standards.