DR. SELWYN E. MAHON M.D.
NPI 1992816169
Emergency Medicine in Tamuning, GU
About Dr. Selwyn E. Mahon M.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. SELWYN E. MAHON M.D. (NPI 1992816169) is an individual emergency medicine provider in Tamuning, Guam, licensed in Virgin Islands (1119) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with University Of Md Shore Medical Ctr At Chestertown, and maintains a secondary practice location in Woonsocket.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
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
Dr. Selwyn E. Mahon M.d. 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
6Medicare enrollment records show Selwyn Mahon reassigns Medicare billing to 6 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Boston, MA 02215
- Reassigned Medicare billing, Massachusetts enrollment
- Also billed through NPI 1861216038 (Massachusetts)
- 253 clinicians in this Medicare group
Chestertown, MD 21620
- Reassigned Medicare billing, Maryland enrollment
- 172 clinicians in this Medicare group
Cambridge, MA 02139
- Reassigned Medicare billing, District of Columbia, Massachusetts, Maryland and Rhode Island enrollments
- Medicare enrollment name: East Harbor Partners PC
- 4 clinicians in this Medicare group
Woonsocket, RI 02895
- Reassigned Medicare billing, Rhode Island enrollment
- 50 clinicians in this Medicare group
Westminster, MD 21157
- Reassigned Medicare billing, Maryland enrollment
- 729 clinicians in this Medicare group
St Thomas, VI 00802
- Reassigned Medicare billing, U.S. Virgin Islands enrollment
- 114 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.
Areas of Expertise CMS Part B claims 3
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
University Of MD Shore Medical Ctr At Chestertown
Acute Care Hospitals · Chestertown, MDPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 96913 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 2
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
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 Selwyn Mahon's NPI number?
The NPI number for Selwyn Mahon is 1992816169. It was assigned to this individual provider in the NPPES registry on August 31, 2006.
Where is Selwyn Mahon located?
Selwyn Mahon practices at 850 Gov. Carlos Camacho Road Guam Memorial Hospital Authority, Tamuning, GU 96913. The listed phone number is (671) 647-2350.
What is Selwyn Mahon's specialty?
The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.
Is Selwyn Mahon enrolled in Medicare?
Yes. Selwyn Mahon 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 Selwyn Mahon's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Selwyn Mahon reassigns Medicare benefits to 6 organizations: Associated Physicians Of Harvard Medical Faculty Physicians At Beth Is (Boston, MA), Chester River Hospital Center (Chestertown, MD), East Harbor Partners, P.C. (Cambridge, MA), Emergency Associates Of Woonsocket LLC (Woonsocket, RI), Emergency Medicine Associates P.A., P.C. (Westminster, MD) and 1 more organization, listed in the Medicare section above. 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 Selwyn Mahon's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Selwyn Mahon accept?
Health plans from Taro Health list Selwyn Mahon 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 Selwyn Mahon affiliated with any hospitals?
According to CMS data, Selwyn Mahon is affiliated with University Of MD Shore Medical Ctr At Chestertown.
When was this NPI record last updated?
The NPPES record for Selwyn Mahon was last updated on August 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 months 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.
# Dr. Selwyn E. Mahon, M.D. · NPI 1992816169
Emergency Medicine physician in Tamuning, GU. Individual provider, active in the CMS NPPES registry since August 31, 2006.
## Identity
- **NPI:** 1992816169 (Entity type: Individual)
- **Enumerated:** August 31, 2006
- **Primary specialty:** Emergency Medicine · taxonomy 207P00000X
- **State license:** 1119 (VI)
- **Sole proprietor:** No
## Practice location
- **Address:** 850 GOV. CARLOS CAMACHO ROAD, GUAM MEMORIAL HOSPITAL AUTHORITY, Tamuning, GU 96913
- **Phone:** (671) 647-2350
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 6 organizations under Medicare reassignment (form CMS-855R): Associated Physicians Of Harvard Medical Faculty Physicians At Beth Is (NPI 1952358533, Boston, MA); Chester River Hospital Center (NPI 1053491795, Chestertown, MD); East Harbor Partners, P.C. (NPI 1720879844, Cambridge, MA); Emergency Associates Of Woonsocket LLC (NPI 1912342528, Woonsocket, RI); Emergency Medicine Associates P.A., P.C. (NPI 1003771320, Westminster, MD); and 1 more · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Howard University College Of Medicine, class of 1990
## Record status
- **NPPES last updated:** August 13, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1992816169) · Data from the CMS NPPES public registry.