Doctor profile · Federal record

Dr. Brennan Mars, PSY.D

Psychologist (CMS: Clinical Psychologist) · Boulder, CO

  • NPI 1013030923
  • Accepts Medicare
  • 30 yrs in practice
  • Female
  • Solo practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
4800 Baseline RD Ste E104 Pmb 344
Boulder, CO 803032643
(303) 358-4603
Mailing address
Pmb 344 4800 Baseline Road, E104
Boulder, CO 80303

Credentials & registration

NPPES · NUCC
NPI registered
April 2007 — 19 yrs on file
Profile last updated
November 16, 2007
Year of graduation
1996 — 30 yrs since
Specialty taxonomy
103T00000X — NUCC code
State license (1)
Colorado #2327
Medicaid
CO #58079831

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1013030923. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
523
Distinct HCPCS
4
Medicare allowed
$65,819
HCPCS Description Services Patients Avg allowed
90837 Psychotherapy, 1 hour 237 18 $128
90837 Psychotherapy, 1 hour 172 19 $146
90834 Psychotherapy, 45 minutes 71 13 $87
90834 Psychotherapy, 45 minutes 43 13 $97

In context: peer comparison

Among 3 peers in Boulder Psychologist, average services per provider: 212. This provider delivers 2.5× the peer median.

Frequently asked questions

Auto-generated from federal data
What is Dr. Brennan Mars's medical specialty?
Dr. Brennan Mars practices Psychologist in Boulder, CO.
Where does Dr. Brennan Mars practice?
Dr. Brennan Mars practices at 4800 Baseline RD Ste E104 Pmb 344, Boulder, CO 803032643. Office phone: 3033584603.
What is Dr. Brennan Mars's NPI?
Dr. Brennan Mars's National Provider Identifier (NPI) is 1013030923, issued by NPPES.
Does Dr. Brennan Mars accept Medicare assignment?
Yes. Dr. Brennan Mars accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Brennan Mars commonly perform?
Top Medicare-reported procedures in 2023: Psychotherapy (HCPCS 90837); Psychotherapy (HCPCS 90837); Psychotherapy (HCPCS 90834). Source: CMS Medicare Physician & Other Practitioners file.