In Medical Billing there is a great deal of confusing terminology that can be intimidating to deal with when first getting started.

One particular confusing item is the Medicare Administrative Contractor (MAC).

A Medicare Administrative Contractor (MAC) is a private healthcare insurer that has been awarded a geographic jurisdiction to process Medicare Part A and Medicare Part B medical claims. They also process Durable Medical Equipment (DME) claims for Medicare Fee-For-Service (FFS) beneficiaries.

MACs typically encompass several states, and their areas are listed on the CMS website.

The 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 perform many activities including:

– Processing 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 (1st stage appeals process)

– Respond to provider inquiries

– Educate providers about Medicare FFS billing requirements

– Establish local coverage determinations (LCD’s)

– Review medical records for selected claims

– Coordinate with CMS and other FFS contractors

In the United States there are 12 A/B MACs and 4 DME MACs that process Medicare FFS claims for nearly 70% of the total Medicare beneficiary population. This amounts to over 37 million Medicare FFS beneficiaries. 

The MACs serve more than 1.5 million health care providers enrolled in the Medicare FFS program, and process more than 1.2 billion Medicare FFS claims annually. This includes over  200 million Part A claims and more than 1 billion Part B claims. The total amount paid Medicare benefits is over $360 billion annually.

(Note: The MAC acronym is also used for the Medicare Administrative Contractor which is a completely different department of Medicare.)