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MARC S WILLIAMS MD
NPI 1992807655
Medical Genetics - Clinical Genetics (M.D.) in Danville, PA

Active since September 02, 2006PECOS Enrolled
100 N ACADEMY AVE, DANVILLE, PA 17822(570) 214-7941(570) 271-5886 Get Directions Write a Review

NPPES record last updated: August 12, 2020. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Marc S Williams Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MARC S WILLIAMS MD (NPI 1992807655) is an individual clinical genetics (m.d.) provider in Danville, Pennsylvania, licensed in Pennsylvania (MD444648) and active in the NPI registry since September 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1992807655
Entity TypeIndividualMale
Primary Taxonomy207SG0201X
Provider Legal NameMARC S WILLIAMSCredential: MD
Location Address100 N ACADEMY AVEDanville, PA 17822-1005
Mailing Address100 N Academy AveDanville, PA 17822-4903 · (570) 271-6144 · Fax (570) 271-6578
Phone(570) 214-7941
Fax(570) 271-5886
Sole ProprietorNo
Enumeration DateSeptember 2, 2006
Last NPPES UpdateAugust 12, 2020
NPPES CertifiedAugust 12, 2020
✔ NPI 1992807655 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyMedical Genetics · Clinical Genetics (M.D.)Allopathic & Osteopathic Physicians
Taxonomy Code207SG0201X
Licenses✔ Licensed in PA · MD444648✔ Licensed in UT · 57601011205
Definition
A clinical geneticist demonstrates competence in providing comprehensive diagnostic, management and counseling services for genetic disorders.
Also ListedPediatricsTaxonomy 208000000X · License 57601018905 (UT), MD444648 (PA)
100 N ACADEMY AVE, Danville, PA 17822
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Buckeye Health Plan, Ambetter Health, Ambetter Health of Delaware.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Marc S Williams Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Marc Williams reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Geisinger Clinic
Same address
Cardiovascular Disease
100 N ACADEMY AVE
Danville, PA 17822
  • Reassigned Medicare billing, Pennsylvania enrollment
  • 4,429 clinicians in this Medicare group
NPI 1013968429 (570) 271-6211

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. TARA JEAN LOUX MD
Surgery (Pediatric Surgery)
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 214-7967
MS. DENISE K HACKMAN RD, LDN
Dietitian, Registered
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-5332
DR. DANIEL CARROLL GEARY MD
Emergency Medicine
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-6212
MS. MONISA DEANNE WAGNER
Physician Assistant
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-7910
JESSICA LYNN CARNEY
Pediatrics
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-7910
CHRISTIE BUONPANE
Surgery (Pediatric Surgery)
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-6211
MAURA ELIZABETH GABLE D.O.
Pediatrics (Neonatal-Perinatal Medicine)
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-7910
ROSLYN MARIE FEASTER
Nurse Anesthetist, Certified Registered
100 N ACADEMY AVE
DANVILLE, PA 17822
Montour County (570) 271-6211

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 Marc Williams's NPI number?

The NPI number for Marc Williams is 1992807655. It was assigned to this individual provider in the NPPES registry on September 2, 2006.

Where is Marc Williams located?

Marc Williams practices at 100 N Academy Ave, Danville, PA 17822. The listed phone number is (570) 214-7941.

What is Marc Williams's specialty?

The primary specialty registered for this NPI is Medical Genetics, specializing in Clinical Genetics (M.D.), with taxonomy code 207SG0201X.

Is Marc Williams enrolled in Medicare?

Yes. Marc Williams is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Marc Williams's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Marc Williams reassigns Medicare benefits to Geisinger Clinic (Danville, PA). 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 Marc Williams's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Marc Williams accept?

Health plans from Ambetter Health, Ambetter Health of Delaware and Ambetter from Buckeye Health Plan list Marc Williams 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.

When was this NPI record last updated?

The NPPES record for Marc Williams was last updated on August 12, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.