NPPES file of Aug 9, 2026

Doctors and health care providers in Fairfield, CA

3,595 individual NPPES records list a practice address in Fairfield, 62nd of 812 California cities. The largest group is behavior technician: 696, 19% of the city's records, against 18% across California. Page 48 of 72.

CMS NPPES registry, file of Aug 9, 2026 · method · Verify with CMS →

The 8 largest groups in Fairfield

Source: CMS NPPES primary taxonomy, file of Aug 9, 2026.

Fairfield in California

  • Rank in California62nd of 812 cities by records
  • Share of the state0.4% of California's records
  • Specialties present25 or more taxonomy codes
  • Top three groups30.3% of all records

Compared with California as a whole, Fairfield has 14.3× the state's share of adult companion records and 0.51× its share of student in an organized health care education/training program records.

Providers in Fairfield, alphabetically

  1. Kathleen Omeara, PH.D.Forensic Psychologist1972906048
  2. Norma Onate, LCSWSocial Worker1366694481
  3. Lana Ayn Ong, PTPhysical Therapist1861846321
  4. Steven Ong, MDNephrology Physician1225006349
  5. Matt OngocoPharmacist1639718158
  6. Daniel OnoePsychologist1568011302
  7. Luis Onofre Valencia, MA, APCCProfessional Counselor1295373520
  8. Chinelo Onwuazombe, FNP-BC, PMHNP-BCPsychiatric/Mental Health Nurse Practitioner1336002393
  9. Tracy OrakpoCounselor1487173381
  10. Alexander OrfinBehavior Technician1588395404
  11. Abigail OrozcoBehavior Technician1922717461
  12. Elizabeth OrozcoCase Manager/Care Coordinator1639215619
  13. Jacqueline OrozcoBehavior Technician1164317145
  14. Julian OrozcoCounselor1588458780
  15. Zaira OrozcoMarriage & Family Therapist1902610132
  16. Rachel Orr, RN, PHNRegistered Nurse1619526787
  17. Matthew OrtegaBehavior Technician1942884499
  18. Michelle Ortega, SUDRCAddiction (Substance Use Disorder) Counselor1366978124
  19. Bertha OrtizCounselor1366745929
  20. Emily OrtizBehavior Technician1114507316
  21. Raymundo OrtizAddiction (Substance Use Disorder) Counselor1902297773
  22. Tayler Ortiz-DixonBehavior Technician1649903675
  23. Samantha OsbornClinical Social Worker1922939263
  24. Melisa OsborneBehavior Technician1376028282
  25. Duaa Oshaik, PHARMDOncology Pharmacist1669227708
  26. Guillermo Osorio Huerta, BCBABehavior Analyst1780222182
  27. Maritza OsterdayAddiction (Substance Use Disorder) Counselor1326446931
  28. Curt Osuga, P.T.Physical Therapist1447332713
  29. Mayra Otero VelasquezBehavior Technician1316718109
  30. Edrick Oteyza, NPNurse Practitioner1619640141
  31. Elizabeth Otong, LCSWClinical Social Worker1477617637
  32. Chelsea OvandoBehavior Technician1528608924
  33. Julie OvertonDoula1376422956
  34. Dexton OwensBehavior Technician1003688250
  35. Hamdat OwohaPsychiatric/Mental Health Nurse Practitioner1487527842
  36. Michael Oyoung, D.C.Chiropractor1265649909
  37. Katherine Pabst, BAMental Health Counselor1376614677
  38. Ashley PachecoPeer Specialist1669131751
  39. Ryan PachecoCommunity Health Registered Nurse1609205764
  40. Brianna PadillaBehavior Technician1730825209
  41. Fernando PadillaLicensed Vocational Nurse1912754847
  42. Heather PadillaBehavior Technician1013606219
  43. Jonard PadillaLicensed Vocational Nurse1225749146
  44. Silvia PadillaCase Manager/Care Coordinator1689529083
  45. Trinidad PadillaCommunity Health Worker1477232379
  46. Vanessa PadillaBehavior Technician1033779970
  47. Ysela PadillaStudent in an Organized Health Care Education/Training Program1407712995
  48. Nancy PadulaAddiction (Substance Use Disorder) Counselor1013370790
  49. Kevin PageOptometrist1316884414
  50. Alexis PagtaloniaBehavior Technician1629824628

The largest California cities

  1. Los Angeles69,537
  2. San Diego52,937
  3. San Francisco38,143
  4. Sacramento33,083
  5. San Jose20,925

All of California →

How to read this directory

Fairfield, California appears in the CMS National Plan and Provider Enumeration System with 3,595 registered healthcare providers spanning 25 or more distinct NUCC-taxonomy specialties. This count includes every individual clinician who has applied for an NPI and listed a practice address in Fairfield - 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 Fairfield practice location on file. Every figure is drawn from the federal National Provider Identifier Registry (CMS NPPES) - more than 7 million providers, maintained since May 2007, with 2024 Medicare Part D data, and, according to CMS, can be searched, compared, and traced in our methodology.

The provider mix in Fairfield is weighted toward Behavior Technician (696 clinicians, followed by Marriage & Family Therapist with 221 and Addiction (Substance Use Disorder) Counselor with 173). 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, Fairfield reports roughly 9.2 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 Fairfield patients, this directory is most useful as a starting shortlist. 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; call the practice directly to confirm the provider is still there, accepts your insurance, and is taking new patients.

For informational purposes only; this directory is not medical advice and not a substitute for checking a license. See also: how to find a doctor and how to verify one.

Common questions

How many doctors are in Fairfield, CA?

There are 3,595 registered healthcare providers in Fairfield, CA, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in Fairfield?

The most common specialties in Fairfield are Behavior Technician, Marriage & Family Therapist, Addiction (Substance Use Disorder) Counselor, Counselor, Clinical Social Worker. Behavior Technician has the most providers with 696.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov). Records are self-reported registrations, not licenses.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.