2026 data CMS NPPES NUCC Taxonomy

Doctors in Fullerton, CA

Active healthcare providers in Fullerton sourced from the CMS NPPES weekly file — no proprietary ratings, no editorial scores. NPI counts, specialty distribution, and primary practice addresses refreshed each release.

5,202
Providers
CMS NPPES-registered
20
Specialties
NUCC taxonomy codes
Behavior Technician
Top specialty
2,133 providers
California
State
CA

5,202 healthcare providers across 20 specialties

Fullerton, California appears in the CMS National Plan and Provider Enumeration System with 5,202 registered healthcare providers spanning 20 distinct NUCC-taxonomy specialties. This count includes every individual clinician who has applied for an NPI and listed a practice address in Fullerton — physicians, dentists, nurse practitioners, physician assistants, chiropractors, physical therapists, optometrists, psychologists, podiatrists, and every other credentialed provider type CMS tracks. It does not measure hospital beds, urgent-care capacity, or whether a given clinic is accepting new patients; it measures the pool of professionals with current NPI enrollment and a Fullerton practice location on file.

The provider mix in Fullerton is weighted toward Behavior Technician (2,133 clinicians, followed by Marriage & Family Therapist with 247 and Student in an Organized Health Care Education/Training Program with 238). That distribution reflects how NPPES records specialty: providers self-select a primary taxonomy code, so a family physician who also practices geriatrics will show up under whichever NUCC code they registered first. Relative to California's population, Fullerton reports roughly 13.4 providers per 100,000 residents using the state-level denominator, which is a rough proxy rather than a precise access-to-care measurement; the true catchment area of any {cityName} clinician extends beyond the municipal boundary.

For Fullerton patients, this directory is most useful as a starting shortlist — searching by specialty narrows the 690-taxonomy roster to clinicians with the relevant training, and each provider page links to NPI, state licensing boards, and the NPPES registry for credential verification. Important: PlainDoctor is a directory of publicly available CMS government data, not a review site, a ranking, or medical advice. NPPES data is self-reported and refreshed monthly, so listing details may be out of date; call the practice directly to confirm the provider is still there, accepts your insurance, and is taking new patients. Nothing on this page substitutes for consulting a licensed clinician about your personal health decisions.

5,202
Providers
20
Specialties
13.4
Per 100K (state)

Which specialties are most common in Fullerton

Behavior Technician 2,133
Marriage & Family Therapist 247
Student in an Organized Health Care Education/Training Program 238
Pharmacist 142
Physician Assistant 127
Rehabilitation Practitioner 112
Mental Health Counselor 111
Acupuncturist 110
Addiction (Substance Use Disorder) Counselor 107
Case Manager/Care Coordinator 96
Clinical Social Worker 92
Optometrist 84
General Practice Dentistry 76
Behavior Analyst 67
Internal Medicine Physician 64
Physical Therapist 59
Chiropractor 58
Dentist 55
Family Nurse Practitioner 51
Clinical Psychologist 49

Healthcare Providers (Page 36)

Name
MARCUS GUILLEN
Behavior Technician
EVELYN GUILLET
Behavior Technician
GORDON GUNN, MD
Gynecology Physician
BRIAN GUNZELMAN, PT, DPT
Physical Therapist
TONY GUO
Behavior Technician
MANMOHAN GURSAHANI, MD
Urology Physician
PATRICIA GUSTI, DDS
General Practice Dentistry
TANYA GUSTIN
Marriage & Family Therapist
ALFREDO GUTIERREZ
Behavior Technician
ANDREA GUTIERREZ
Behavior Technician
ANDREW GUTIERREZ
Case Manager/Care Coordinator
BRIAN GUTIERREZ
Behavior Technician
ELVIRA GUTIERREZ
Behavior Technician
ERICA GUTIERREZ
Behavior Technician
KAREEN GUTIERREZ
Student in an Organized Health Care Education/Training Program
LINDA GUTIERREZ
Behavior Technician
MARASTELLA GUTIERREZ
Student in an Organized Health Care Education/Training Program
MARIA GUTIERREZ
Behavior Technician
MATTHEW ALLEN GUTIERREZ
Student in an Organized Health Care Education/Training Program
MAXIMILIANO GUTIERREZ
Behavior Technician
REBECCA GUTIERREZ
Behavior Technician
SADE GUTIERREZ
Behavior Technician
STEPHANIE GUTIERREZ
Behavior Technician
VALERIE GUTIERREZ, B.A.
Rehabilitation Practitioner
BELEN GUTIERREZ BAROBIO
Behavior Technician
CRISTINA GUTIERREZ VILLAVICENCIO
Behavior Technician
CONNOR GUTIERREZ-RAY
Behavior Technician
BRIAN GUZMAN
Addiction (Substance Use Disorder) Counselor
BRIANA GUZMAN
Rehabilitation Practitioner
DAVID GUZMAN
Community Health Worker
ELIZABETH GUZMAN
Behavior Technician
JUANA GUZMAN
Behavior Analyst
KAREN GUZMAN
Behavior Technician
LUPITA GUZMAN
Behavior Technician
CITLALI GUZMAN-CREANO
Behavior Technician
ANDREW HA
Pharmacist
REGINA HA, PA-C
Physician Assistant
GORDON HAAG, D.D.S.
General Practice Dentistry
JASON HAAKINSON, PHARMD
Pharmacist
ARNOLD RYAN HABAN
Registered Nurse
PETER HABIB
Behavior Technician
GIORGIO HADDAD
Student in an Organized Health Care Education/Training Program
KIMBERLY HAGAN, PHD
Clinical Psychologist
AARON HAGEMAN
Behavior Technician
HANNAH HAHN
Physician Assistant
LEILA HAJKAZEMSHIRAZI
Optometrist
DANIELLE HALEWIJN
Registered Dietitian
MELISA HALFMANN
Behavior Technician
WILLIAM HALL, PA-C
Surgical Physician Assistant
MAUREEN HALL-KATZ, M.A., CCC-SLP
Speech-Language Pathologist

Nearby Cities in California

Other California cities with provider coverage in the CMS NPPES registry.

Compare specialties side-by-side →

Frequently Asked Questions

How many doctors are in Fullerton, CA?
There are 5,202 registered healthcare providers in Fullerton, CA, covering 20 specialties. This includes physicians, dentists, therapists, and other licensed providers.
What are the most common medical specialties in Fullerton?
The most common specialties in Fullerton are Behavior Technician, Marriage & Family Therapist, Student in an Organized Health Care Education/Training Program, Pharmacist, Physician Assistant. Behavior Technician has the most providers with 2,133.

Provider data from CMS NPPES (download.cms.gov/nppes); specialty classification from NUCC Health Care Provider Taxonomy. PlainDoctor does not rate or rank providers. Methodology · About

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from CMS National Plan and Provider Enumeration System (NPPES). Consult a qualified professional before making decisions based on this data.