The Basics of Medicare Administrative Contractors (MACs)

By Jeffery Olson posted 14 days ago


On behalf of the ASHP SAG on Compensation and Practice Sustainability this blog post was written by Kelsey Kelsch, PharmD Candidate while on rotation with me on an Ambulatory Care Administration rotation at Intermountain Healthcare in Salt Lake City, UT. I want to also acknowledge the contributions of Monica Rauch, PharmD, BCACP who was a PGY2 Ambulatory Care Resident at Intermountain Healthcare during the time this was written. I hope you enjoy reading the valuable information included.


As a pharmacy student on rotation, the topic of Medicare Administrative Contractors (MACs) was discussed in a meeting I attended. During that meeting, I sensed that MACs were important, but I didn’t fully understand their role so my preceptor offered me the opportunity to do more research on the topic. I believed that research could be valuable to others so I wanted to share it.


What is a Medicare Administrative Contractor (MAC)?

MACs were created as a result of the Medicare Prescription Drug Improvement and Modernization Act of 2003. This act aimed to improve prescription drug coverage and subsequently reduce the financial burden of medications for beneficiaries. MACs are third parties that process Medicare fee-for-service (FFS) Part A/B, durable medical equipment (DME), and home-health and hospice claims for a specific geographic region known as a jurisdiction. Additionally, they act as an intermediary between Medicare and healthcare providers.


What responsibilities do MACs have?

MACs perform a variety of roles including items listed below:


  • Process Medicare Part A/B, DME, and home health and hospice claims
  • Coordinate between Centers for Medicare & Medicare Services and FFS contractors
  • Define local coverage determinations
  • Manage billing requirements and make Medicare FFS payments
  • Facilitate provider enrollment, educate/train providers, and respond to their inquiries
  • Handle first level appeals for denied claims
  • Provide Medicare with data on cost, quality, and timeliness of services


For additional roles, please use the following link:


How can you identify your MAC?

In total, there are 16 MACs. Eight MACs manage Part A/B claims, 4 manage DME claims, and 4 manage Part A/B claims in addition to home health and hospice claims. Each MAC has their own unique jurisdiction for each type of claim service they provide and therefore you may need to work with multiple MACs depending on your state. To identify your jurisdiction and subsequent MAC(s), utilize the following link:


Why should you engage with your MAC?

Pharmacists must comply with the often-complex Medicare prescription and billing requirements. Each MAC can have different billing requirements for DME supplies or clinical services based upon their unique interpretation of Medicare regulations. Pharmacists should work with their MAC to identify and establish compliance with various requirements and regulations that apply to their services. Partnering with your MAC can be especially important when implementing a clinical service and as new health care regulations are passed. This partnership can help ensure appropriate compliance and eligibility for reimbursement. Reimbursement for clinical pharmacy services remains a prominent challenge without provider status. However, pharmacists can work with MACs to navigate reimbursement challenges and ultimately improve the sustainability of their clinical pharmacy service(s).


Where can more information about MACs be found?

The following link can provide more information:



  • Kliethermes M. Understanding health care billing basics. Pharm Today. 2017; 23(7): 57-68. Available at: Accessed April 22, 2018.
  • Medicare Administrative Contractors. AHCA: American Health Care Association. Available at: Published 2018. Accessed April 22, 2018.
  • What is a MAC. Centers for Medicare & Medicaid Services. Available at: Published October 26, 2017. Accessed April 22, 2018.
  • Who are the MACs. Centers for Medicare & Medicaid Services. Available at: Accessed April 22, 2018.