NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Dr. Roger W Marcus, MD

Rheumatology Physician in Fallston, MD · enumerated 2006.

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

National Provider Identifier

1588779672

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)
Name Dr. Roger W Marcus
Credential MD
Sex Male
Practice address 1814 Bel Air Rd, Fallston, MD, 21047
Phone (410) 877-0271
Fax (410) 877-0274
Enumeration date Aug 20, 2006
Last updated in NPPES Jan 16, 2013

Taxonomy & licenses

207RR0500X Rheumatology Physician Allopathic & Osteopathic Physicians · License D23646 (MD) 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
777011100 Medicaid MD -

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.

Read the full guide → Validate an NPI →

Frequently asked questions

What is the NPI number for Roger Marcus?
The National Provider Identifier (NPI) for Roger Marcus is 1588779672, a Type 1 (individual) record in the CMS NPPES registry.
Where does Roger Marcus practice?
The practice location on file with NPPES is in Fallston, MD. Providers can have multiple locations; NPPES lists the primary practice address.

Other providers at this practice address

Browse all →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2013-01-16.