Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Mark Allan Walker Jr., O.D.
Optometrist in Elkhart, IN · enumerated 2009.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1972731461
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Registry record
Entity type Individual (Type 1)
Name Dr. Mark Allan Walker Jr.
Credential O.D.
Sex Male
Practice address 2746 Old Us 20 W, Elkhart, IN, 46514
Phone (574) 293-3545
Fax (574) 522-0599
Enumeration date Jun 23, 2009
Last updated in NPPES Nov 8, 2012
Taxonomy & licenses
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses.
About the OD credential
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.
Frequently asked questions
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.
What specialty is Mark Walker?
Mark Walker is registered in NPPES with the primary taxonomy of Optometrist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Other providers at this practice address
Browse all → Richard Boling Ophthalmology Physician · Elkhart, IN NPI 1245278068 Boling Vision Center, LLC Ophthalmology Physician · Elkhart, IN NPI 1003851445 Amy Layman Optometrist · Elkhart, IN NPI 1215965454 Kevin Egan Optometrist · Elkhart, IN NPI 1902837339 Elkhart Neurology PC Neurology Physician · Elkhart, IN NPI 1306976717 Boling Vision Center, LLC Eyewear Supplier · Elkhart, IN NPI 1336272673 Whitney Boling Ophthalmology Physician · Elkhart, IN NPI 1629333133
Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2012-11-08.