Medicare Administrative Contractor (MAC): Jurisdictions Explained
A Medicare Administrative Contractor is a private company CMS contracts to process Fee-for-Service Medicare claims for a defined jurisdiction. Twelve A/B MACs handle Part A and Part B by geographic region, and four DME MACs handle durable medical equipment nationally by region. Your MAC controls your LCDs, local billing rules, and appeals routing.
- A/B MACs
- 12, by geographic jurisdiction
- DME MACs
- 4 (Jurisdictions A, B, C, D)
- What they set
- LCDs, local edits, appeals routing
- Confirm here
- CMS "Who are the MACs" page
What is a Medicare Administrative Contractor?
A MAC is a private company that CMS pays to run Fee-for-Service (Original) Medicare in a defined territory. The MAC enrolls providers, processes and pays claims, applies local edits, publishes coverage policy, and handles the first level of appeals. CMS sets the rules; the MAC operates them for its slice of the country. Every Part A, Part B, and DME claim in Original Medicare is adjudicated by one of these contractors.
There are two kinds. Twelve A/B MACs process Part A (hospital and facility) and Part B (physician and outpatient) claims for the states in their geographic jurisdiction. Four DME MACs process durable medical equipment, prosthetics, orthotics, and supplies claims nationally, split into four regional jurisdictions (A, B, C, and D), billed by the beneficiary's permanent residence.
Why does the jurisdiction matter?
Because much of what decides whether a claim pays is set locally, not nationally. Your MAC writes the Local Coverage Determinations and billing-and-coding articles that define covered diagnoses, frequency limits, and documentation for everything no National Coverage Determination addresses. The same test can be covered under one MAC's LCD and have no LCD at all under another, so a diagnosis that pays in Texas may deny in Florida.
Jurisdiction also controls operations: which portal you check status in, where paper claims and records go, and where a redetermination appeal is routed. Address an appeal to the wrong MAC and it does not get forwarded quietly; it is a wasted filing against a 120-day clock.
Which MAC covers which states?
The 12 A/B MAC jurisdictions and their current contractors are below. Contracts are recompeted on multi-year cycles, so confirm any assignment on the CMS "Who are the MACs" page before relying on it. DME is separate: Noridian holds Jurisdictions A (Northeast) and D (West); CGS holds Jurisdictions B (Midwest) and C (South).
| Jurisdiction | Contractor | States / region |
|---|---|---|
| JE | Noridian Healthcare Solutions | CA, HI, NV, plus Guam, American Samoa, N. Mariana Islands |
| JF | Noridian Healthcare Solutions | AK, AZ, ID, MT, ND, OR, SD, UT, WA, WY |
| J5 | WPS (Wisconsin Physicians Service) | IA, KS, MO, NE |
| J8 | WPS (Wisconsin Physicians Service) | IN, MI |
| J6 | National Government Services (NGS) | IL, MN, WI |
| JK | National Government Services (NGS) | CT, ME, MA, NH, NY, RI, VT |
| J15 | CGS Administrators | KY, OH |
| JH | Novitas Solutions | AR, CO, LA, MS, NM, OK, TX |
| JL | Novitas Solutions | DE, DC, MD, NJ, PA |
| JJ | Palmetto GBA | AL, GA, TN |
| JM | Palmetto GBA | NC, SC, VA, WV |
| JN | First Coast Service Options | FL, PR, U.S. Virgin Islands |
If any assignment looks off, treat the CMS page as authoritative and do not guess. A MAC transition can move LCDs, portals, and mailing addresses at once, and billing to the outgoing contractor after the cutover date produces rejections that are avoidable with a quick check. The companion how to find your MAC and LCD entry walks through confirming yours before you submit.
Frequently asked questions
An A/B MAC processes Part A (facility) and Part B (professional) claims for the states in its geographic jurisdiction. A DME MAC processes durable medical equipment, prosthetics, orthotics, and supplies claims nationwide, split into four regional jurisdictions. A supplier bills the DME MAC for the region where the beneficiary permanently resides, not where the item was dispensed.
For Part A and Part B, it is the A/B MAC for the state where the service was furnished. For DME, it is the DME MAC for the beneficiary's permanent residence. The authoritative source is the CMS "Who are the MACs" pages, which list each jurisdiction, its contractor, and its states. Verify there rather than relying on memory, because contracts change.
Yes. CMS recompetes MAC contracts on multi-year cycles, so a jurisdiction can move to a new contractor, and jurisdiction lines have been redrawn over time. When a MAC transitions, LCDs, provider portals, and mailing addresses can all change. Watch your current MAC's bulletins and the CMS "Who are the MACs" page for transition notices before they affect your claims.
Sources & further reading
Reviewed by the ImmediCare Solutions RCM team
Certified billers and coders handling claims across 50+ specialties nationwide. This entry is reviewed against current payer policy and CMS rules. Last review: Jul 5, 2026.
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