Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Michael Grillon, MD

Family Medicine Physician in Onancock, VA · enumerated 2005 · practices at Riverside Physician Services Inc.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1639178122

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Registry record

Entity type Individual (Type 1)

Name Michael Grillon

Credential MD

Sex Male

Practice address 20486 Market Street, Onancock, VA, 23417

Phone (757) 302-2700

Fax (757) 787-9262

Enumeration date Jul 18, 2005

Last updated in NPPES Nov 11, 2019

Taxonomy & licenses

208600000X Surgery Physician Allopathic & Osteopathic Physicians · License 0101055534 (VA) Secondary

207Q00000X Family Medicine Physician Allopathic & Osteopathic Physicians · License 0101055534 (VA) Primary

MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier	Type	State	Issuer
C06115	Other	VA	GROUP PTAN
1073988	Other	WV	BRICKSTREET-WV COMP
1639178122	Medicaid	VA	-
020002600	Other	VA	BLACK LUNG
2132448	Other	VA	MAMSI
5472512	Other	VA	AETNA
790577T	Medicaid	NC	-
1373138	Other	VA	CIGNA
178223	Other	VA	BCBS
3810012912	Medicaid	WV	-

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What specialty is Michael Grillon?

Michael Grillon is registered in NPPES with the primary taxonomy of Family Medicine Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Is this the official NPI registry?

No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.

Other providers at this practice address

Browse all →

David Jones Critical Care Medicine (Internal Medicine) Physician · Onancock, VA NPI 1194712414 Ashan Manohar Gastroenterology Physician · Onancock, VA NPI 1295725836 Alexander Schult Pulmonary Disease Physician · Onancock, VA NPI 1871573568 Debra Spatz Orthopaedic Surgery Physician · Onancock, VA NPI 1932175288 Ghias Rana Obstetrics & Gynecology Physician · Onancock, VA NPI 1497722839 Thomas Hare Physician Assistant · Onancock, VA NPI 1164440087 Debra Myers Family Nurse Practitioner · Onancock, VA NPI 1235208471 Jack Lambert Urology Physician · Onancock, VA NPI 1518128453

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2019-11-11.