Definition: A Medicare Administrative Contractor (MAC) is a private organization responsible for managing policies and processing Medicare Part A, Medicare Part B, and durable medical equipment (DME) claims for Medicare Fee-For-Service (FFS) beneficiaries.¹ CMS relies on a network of MACs to serve as the primary operational contact between the Medicare FFS program and the health care providers enrolled in the program. MACs are multistate regional contractors responsible for many activities, including:

• Process Medicare FFS claims
• Make and account for Medicare FFS payments
• Enroll providers in the Medicare FFS program
• Handle provider reimbursement services and audit institutional provider cost reports
• Handle redetermination requests (first stage appeals process)
• Respond to provider inquiries
• Educate providers about Medicare FFS billing requirements
• Establish local coverage determinations (LCDs)
• Review of medical records for selected claims
• Coordinate with CMS and other FFS contractors

Find your local MAC: Twelve regional MACs are assigned to manage Medicare Part A and B claims, four of which have additional jurisdictions for processing home health and hospice (HH+H) claims. Durable medical equipment, orthotics, and prosthetics (DMEPOS) claims are processed through a separate MAC, with four jurisdictions assigned in the United States.

• A/B MAC jurisdiction map
• HH+H MAC jurisdiction map
• DME MAC jurisdiction map
• MACs by state

How it relates to quality-based care: MACs assist providers, including pharmacists, who are working under ACOs/PCMHs to answer questions related to claims and billing for services provided to Medicare FFS beneficiaries. Any claims submitted by an ACO/PCMH are processed through the designated MAC in that region. Pharmacists who work on drug coverage for Part B should be familiar with their MACs' LCD guidance to facilitate acceptance of claims and/or to assist with appeals.

Not all ACOs are contracted with a pharmacy or have a formal relationship with one. However, ACOs contracting pharmacies have a broader range of services and greater experience with payment reform.³ Pharmacies contracted with a MAC can be reimbursed for covered Medicare Part B services such as immunizations, tests, and diabetes self-management training.

Involved organizations/oversight: CMS procures and manages MAC contracts under the Federal Acquisition Regulation and HHS Acquisition Regulation requirements. Each MAC is also required to have its own compliance program.

Resources

1. CMS. Medicare administrative contractors. Baltimore: CMS. Available at: www.cms.gov/medicare/coding-billing/medicare-administrative-contractors-macs. Accessed October 11, 2024.
2. Congress.gov. H.R. 1–Medicare Prescription Drug, Improvement, and Modernization Act of 2003. Washington, DC: U.S. Congress. Available at: www.congress.gov/bill/108th-congress/house-bill/1. Accessed March 10, 2023.
3. Colla CH, Lewis VA, Beaulieu-Jones BR, et al. Role of pharmacy services in accountable care organizations. J Manag Care Spec Pharm. 2015;21(4):338–44.
4. Petrovskis MG, Misita C, Merine LB. The Pharmacists Role in Ensuring Revenue Integrity. Pharmacy Purchasing & Products. 2018;15(12).

Contributing authors

Sara Touchan, PharmD
PGY-1 Pharmacy Practice Resident
Wentworth-Douglass Hospital
Dover, NH

Amber Mercuro, PharmD, BCACP
Clinical Ambulatory Pharmacist
Wentworth-Douglass Hospital
Dover, NH

Last Updated on 10/11/2023: Pam Lincoln-Giang, PharmD, BCGP, Sr. Director, Pharmacy, WelbeHealth