NPI Portal NPI Lookup & Verification

Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum Sole proprietor

Dr. Mark Robert Helmus, O.D.

Optometrist in Davis, CA · enumerated 2005.

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

National Provider Identifier

1558343905

Verified

See something wrong? Report a correction

Registry record

Entity type Individual (Type 1)
Name Dr. Mark Robert Helmus
Credential O.D.
Sex Male
Practice address Davis, CA, 95616
Phone (530) 758-2122
Fax (530) 758-1448
Enumeration date Nov 18, 2005
Last updated in NPPES Oct 28, 2011

Street address withheld: NPPES sole-proprietor addresses can be home addresses. See our data policy.

Taxonomy & licenses

152W00000X Optometrist Eye and Vision Services Providers · License OPT 00007215 TPA (CA) Secondary
152W00000X Optometrist Eye and Vision Services Providers · License OPT7215TPA (CA) Primary
OD · Doctor of Optometry: A licensed optometrist providing primary vision care, eye exams, and corrective lenses. About the OD credential

Other identifiers

Identifier Type State Issuer
ZZZ58352Z Other CA BS OF CA
SD0072150 Medicaid CA -
4046062 Other TN BC/BS OF TENNESSEE

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

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 Helmus?
Mark Helmus 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 →

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2011-10-28.