The Centers for Medicare & Medicaid Services (CMS) contracts with Medicare Administrative Contractors (MACs) to serve as the primary operational contact between the Medicare Fee-For-Service program and the healthcare providers enrolled in the program. MACs are responsible for processing and paying claims for both Medicare Part A (e.g., hospital, skilled nursing facility) and Part B (e.g., physician services, outpatient care) for a specific geographic jurisdiction. Their role is fundamental to the administration of the Medicare program.

A. Recovery Audit Contractors (RACs) are tasked with identifying and recovering improper Medicare payments after they have been processed and paid.

B. Risk Adjustment Validation (RADV) contractors are used by CMS to audit and validate risk adjustment data submitted by Medicare Advantage Organizations.

D. Zone Program Integrity Contractors (ZPICs), now succeeded by Unified Program Integrity Contractors (UPICs), focus on investigating fraud, waste, and abuse.

1. Centers for Medicare & Medicaid Services (CMS). (n.d.). Medicare Administrative Contractor (MAC). CMS.gov. Retrieved from https://www.cms.gov/Medicare/Medicare-Contracting/Medicare-Administrative-Contractors/MedicareAdministrativeContractors. This official CMS page defines the role of MACs, stating they "process Medicare Part A and Part B medical claims or Durable Medical Equipment (DME) claims."

2. Centers for Medicare & Medicaid Services (CMS). (2023, October). Medicare Program Integrity Manual. Chapter 1 - Introduction, Section 1.2. This manual details the roles of various contractors, distinguishing the claims processing function of MACs from the integrity and audit functions of RACs and ZPICs/UPICs.