MARY BRENNA MCMAHON LMSW
NPI 1558828897
Social Worker in Ann Arbor, MI
About Mary Brenna Mcmahon Lmsw NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARY BRENNA MCMAHON LMSW (NPI 1558828897) is an individual social worker in Ann Arbor, Michigan, licensed in Michigan (6801109270) and active in the NPI registry since February 2019. She is enrolled in Medicare PECOS, is affiliated with University Of Michigan Health System, and is a graduate of Other (2018).
NPPES Registry Identity
Specialties & Licenses
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Mary Brenna Mcmahon Lmsw is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
2Medicare enrollment records show Mary Mcmahon reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Ann Arbor, MI 48109
- Reassigned Medicare billing, Michigan enrollment
- 80 clinicians in this Medicare group
Ann Arbor, MI 48104
- Reassigned Medicare billing, Michigan enrollment
- 3 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
University Of Michigan Health System
Acute Care Hospitals · Ann Arbor, MIOther Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
ANN ARBOR, MI 48109
ANN ARBOR, MI 48109
ANN ARBOR, MI 48109
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Mary Mcmahon's NPI number?
The NPI number for Mary Mcmahon is 1558828897. It was assigned to this individual provider in the NPPES registry on February 22, 2019.
Where is Mary Mcmahon located?
Mary Mcmahon practices at 4260 Plymouth Rd, Ann Arbor, MI 48109. The listed phone number is (734) 764-6831.
What is Mary Mcmahon's specialty?
The primary specialty registered for this NPI is Social Worker with taxonomy code 104100000X.
Is Mary Mcmahon enrolled in Medicare?
Yes. Mary Mcmahon is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Mary Mcmahon's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mary Mcmahon reassigns Medicare benefits to 2 organizations: Regents Of The University Of Michigan (Ann Arbor, MI) and Cycle Breakers Collective LLC (Ann Arbor, MI). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Mary Mcmahon's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Mary Mcmahon accept?
Health plans from Ambetter Health, Ambetter from Buckeye Health Plan, Ambetter from Meridian, Blue Care Network of Michigan and Blue Cross Blue Shield of Michigan Mutual Insurance Company and 1 other insurer list Mary Mcmahon as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
Is Mary Mcmahon affiliated with any hospitals?
According to CMS data, Mary Mcmahon is affiliated with University Of Michigan Health System.
When was this NPI record last updated?
The NPPES record for Mary Mcmahon was last updated on October 1, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Mary Brenna Mcmahon, LMSW · NPI 1558828897
Social Worker provider in Ann Arbor, Michigan. Individual provider, active in the CMS NPPES registry since February 22, 2019.
## Identity
- **NPI:** 1558828897 (Entity type: Individual)
- **Enumerated:** February 22, 2019
- **Primary specialty:** Social Worker · taxonomy 104100000X
- **State license:** 6801109270 (Michigan)
- **Sole proprietor:** No
## Practice location
- **Address:** 4260 PLYMOUTH RD, Ann Arbor, MI 48109-2700
- **Phone:** (734) 764-6831
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): Regents Of The University Of Michigan (NPI 1356366868, Ann Arbor, MI); Cycle Breakers Collective LLC (NPI 1497510655, Ann Arbor, MI) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2018
## Record status
- **NPPES last updated:** October 1, 2021
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Source: [NPI Profile](https://npiprofile.com/npi/1558828897) · Data from the CMS NPPES public registry.