WILLIAM X NGHIEM MD
NPI 1851559223
Radiology - Vascular & Interventional Radiology in Germantown, MD
About William X Nghiem Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
WILLIAM X NGHIEM MD (NPI 1851559223) is an individual vascular & interventional radiology provider in Germantown, Maryland, licensed in Maryland (D78132) and active in the NPI registry since June 2008. He is enrolled in Medicare PECOS, is affiliated with Frederick Health Hospital, and is a graduate of Temple University School Of Medicine (2008).
NPPES Registry Identity
Specialties & Licenses
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
William X Nghiem Md 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 Reassignment
Medicare enrollment records show William Nghiem reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Germantown, MD 20876
- Reassigned Medicare billing, District of Columbia and Maryland enrollments
- 9 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 8
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.
Frederick Health Hospital
Acute Care Hospitals · Frederick, MDPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 20876 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Medicare Quality Performance CMS QPP · MIPS
Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.
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.
GERMANTOWN, MD 20876
GERMANTOWN, MD 20876
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 William Nghiem's NPI number?
The NPI number for William Nghiem is 1851559223. It was assigned to this individual provider in the NPPES registry on June 1, 2008.
Where is William Nghiem located?
William Nghiem practices at 20410 Observation Dr Ste 100, Germantown, MD 20876. The listed phone number is (301) 762-0277.
What is William Nghiem's specialty?
The primary specialty registered for this NPI is Radiology, specializing in Vascular & Interventional Radiology, with taxonomy code 2085R0204X.
Is William Nghiem enrolled in Medicare?
Yes. William Nghiem 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 organization bills Medicare for William Nghiem's services?
According to the CMS Revalidation Reassignment List (October 2026 release), William Nghiem reassigns Medicare benefits to Horizon Surgical Group, PA (Germantown, MD). The 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 William Nghiem's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
Is William Nghiem affiliated with any hospitals?
According to CMS data, William Nghiem is affiliated with Frederick Health Hospital.
When was this NPI record last updated?
The NPPES record for William Nghiem was last updated on November 4, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 days 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.
# William X Nghiem, MD · NPI 1851559223
Vascular & Interventional Radiology physician in Germantown, Maryland. Individual provider, active in the CMS NPPES registry since June 1, 2008.
## Identity
- **NPI:** 1851559223 (Entity type: Individual)
- **Enumerated:** June 1, 2008
- **Primary specialty:** Radiology - Vascular & Interventional Radiology · taxonomy 2085R0204X
- **State license:** D78132 (Maryland)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 20410 OBSERVATION DR STE 100, Germantown, MD 20876-6419
- **Phone:** (301) 762-0277 · **Fax:** (301) 330-9108
## 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:** Horizon Surgical Group, PA (NPI 1366449365, Germantown, MD), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Temple University School Of Medicine, class of 2008
## Record status
- **NPPES last updated:** November 4, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1851559223) · Data from the CMS NPPES public registry.