NPI Portal NPI Lookup & Verification

Dr. Brennan Lynn Mars, PSY.D

Dr. Brennan Lynn Mars is a Psychologist provider (Psychologist) practicing in Boulder, CO, registered in the NPPES registry with NPI 1013030923 since 2007. The credential PSYD stands for Doctor of Psychology.

✓ Active NPI ✓ Valid NPI checksum Sole proprietor

NPI 1013030923
Entity type Individual (Type 1)
Name Dr. Brennan Lynn Mars
Credential PSY.D
Sex Female
Practice address Boulder, CO, 80303
Phone 3033584603
Enumeration date 2007-04-06
Last updated in NPPES 2007-11-16

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

Taxonomy & licenses

Taxonomy code Specialty Primary License State
103T00000X Psychologist Primary 2327 CO

PSYD — Doctor of Psychology: A clinical doctorate in psychology focused on professional practice. About the PSYD credential

Other identifiers

Identifier Type State Issuer
58079831 Medicaid CO
Copy-ready billing details
Provider: Brennan Mars, PSY.D
NPI: 1013030923
Taxonomy: 103T00000X (Psychologist)
Address: Boulder, CO, 80303

Verify this record

Cross-check NPI 1013030923 against the authoritative CMS record: view Dr. Brennan Lynn Mars on the official NPPES registry .

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 or validate an NPI number.

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 Brennan Mars?
Brennan Mars is registered in NPPES with the primary taxonomy of Psychologist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2007-11-16.