Written and maintained by CASRAI Editorial Board
Last updated
Short answer: A DME MAC is a Medicare Administrative Contractor that processes Medicare claims for durable medical equipment, orthotics and prosthetics (DMEPOS) within a defined geographic jurisdiction. CMS describes four DME MAC jurisdictions, A, B, C and D, and separate A/B MACs for other Part A and Part B claims. This page is general information, not medical or billing advice.
Definition and scope
CMS defines a Medicare Administrative Contractor (MAC) as a private health care insurer that has been awarded a geographic jurisdiction to process Medicare Part A and Part B claims. A DME MAC is the kind of MAC that processes Medicare DMEPOS claims for its jurisdiction, and it serves DMEPOS suppliers. CMS lists four DME MACs and 12 A/B MACs (CMS, “What is a MAC?”, checked 2026-10-30).
CMS describes a MAC as a private health care insurer awarded a geographic jurisdiction, so a DME MAC works under contract for CMS.
What is DME in healthcare?
DME stands for durable medical equipment. In Medicare contracting, CMS groups it with orthotics and prosthetics as DMEPOS, the claim category that DME MACs handle. The durable medical equipment list shows how the category is organised, and the Medicare DME coverage guide covers what Medicare reimburses.
What does a DME MAC do?
CMS lists these functions for MACs in general, which apply to a DME MAC for DMEPOS claims in its jurisdiction:
- Process fee-for-service claims and make and account for payments.
- Enroll providers in fee-for-service Medicare.
- Establish local coverage determinations (LCDs).
- Educate providers about Medicare fee-for-service billing requirements.
- Handle first-stage appeals, called redeterminations.
Source: CMS, “What is a MAC?” (page last modified 2026-07-08; checked 2026-10-30).
The four DME MAC jurisdictions
CMS identifies four DME MAC jurisdictions: A (JA), B (JB), C (JC) and D (JD). Each has its own page on cms.gov, and CMS publishes a DME MAC jurisdiction map and a “MACs by State” list as PDFs (CMS, “Who are the MACs?”, checked 2026-10-30). The CMS list page does not name the contractors, so check the current CMS pages for who holds each jurisdiction.
As one worked example of how a jurisdiction is defined, the Noridian JD DME jurisdiction list (last updated 2026-01-15, checked 2026-10-30) names these states and territories for Jurisdiction D: American Samoa, Guam, Northern Mariana Islands, Alaska, Arizona, California, Hawaii, Idaho, Iowa, Kansas, Missouri, Montana, Nebraska, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming. The same page notes that year-specific lists help suppliers determine which Medicare contractor to bill for certain HCPCS codes.
DME MAC compared with an A/B MAC
| Question | DME MAC | A/B MAC |
|---|---|---|
| What it processes | Medicare DMEPOS claims | Medicare Part A and Part B claims |
| Number CMS lists | 4 jurisdictions | 12 jurisdictions |
| Who it mainly serves | DMEPOS suppliers | Providers of Part A and Part B services |
| Shared MAC functions | Claims processing and payment, enrollment, LCDs, provider education, redeterminations | |
Source for every row: CMS, “What is a MAC?” (checked 2026-10-30).
Where a DME MAC matters for labs, clinics and supply decisions
Staff who deal with Medicare-covered equipment meet the DME MAC in three places. This checklist ties each to the related page on this site.
- Coverage rules: MACs establish the local coverage determinations that apply to a category of items, so coverage questions for a DMEPOS item lead to the LCD issued for the relevant jurisdiction. See the Medicare DME coverage guide.
- Accreditation: CMS accreditation requirements for DMEPOS suppliers connect to billing DME MACs. See DMEPOS accreditation, which cites CMS MLN905710 (December 2025).
- Codes: HCPCS codes identify the item on a claim, and contractor policy documents are written around them. See HCPCS E0601 for a worked example of a single code.
Common misunderstandings
- A DME MAC is not Medicare itself. CMS describes a MAC as a private health care insurer awarded a geographic jurisdiction.
- There is one DME MAC for the whole country. CMS lists four jurisdictions, each with its own page.
- DME MACs handle every Medicare claim. They handle DMEPOS claims; A/B MACs process Part A and Part B claims for their jurisdictions.
- Old jurisdiction lists stay current. CMS’s state list PDF is dated, and the Noridian page carries its own update date, so check the current CMS pages before relying on any list.
FAQ
What is DME in healthcare?
DME means durable medical equipment. In Medicare administration it is grouped with orthotics and prosthetics as DMEPOS, which DME MACs process for their jurisdictions. See the durable medical equipment list.
What does DME MAC stand for?
Durable Medical Equipment Medicare Administrative Contractor. CMS describes it as the MAC that processes Medicare DMEPOS claims for a defined geographic jurisdiction.
How many DME MACs are there?
CMS lists four DME MACs, covering Jurisdictions A, B, C and D, alongside 12 A/B MACs (checked 2026-10-30).
Sources
- CMS, What is a MAC?, last modified 2026-07-08, checked 2026-10-30.
- CMS, Who are the MACs?, last modified 2024-09-10, checked 2026-10-30.
- Noridian Healthcare Solutions, Jurisdiction D DME jurisdiction list, updated 2026-01-15, checked 2026-10-30.
