NPPES file of Aug 9, 2026

Doctors and health care providers in Costa Mesa, CA

4,286 individual NPPES records list a practice address in Costa Mesa, 48th of 812 California cities. The largest group is behavior analyst: 1,239, 29% of the city's records, against 2% across California. Page 56 of 86.

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

The 8 largest groups in Costa Mesa

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

Costa Mesa in California

  • Rank in California48th of 812 cities by records
  • Share of the state0.4% of California's records
  • Specialties present25 or more taxonomy codes
  • Top three groups55.2% of all records
  • Behavior Analyst rank1st of the 10 California cities with the most

Compared with California as a whole, Costa Mesa has 13.8× the state's share of behavior analyst records and 0.27× its share of case manager/care coordinator records.

Providers in Costa Mesa, alphabetically

  1. James Nguyen, RPHPharmacist1306971700
  2. John Nguyen, D.D.S.Dentist1518394675
  3. Joseph NguyenBehavior Technician1073070256
  4. Julia NguyenBehavior Technician1013555176
  5. Kaitlyn Nguyen, MS LMFTMarriage & Family Therapist1710402649
  6. Kathy NguyenBehavior Analyst1982390977
  7. Kayla NguyenBehavior Technician1801741459
  8. Keren Nguyen, DDSDentist1477761708
  9. Kevin NguyenBehavior Technician1164989067
  10. Kimberly Nguyen, DOPain Medicine Physician1952780983
  11. Lam NguyenBehavior Technician1649959180
  12. Lethuy Nguyen, BCBABehavior Analyst1457852089
  13. Lisa NguyenBehavior Analyst1952116162
  14. Lynn NguyenBehavior Technician1811456239
  15. Mandy NguyenFamily Medicine Physician1548849979
  16. Megan NguyenBehavior Analyst1063398907
  17. Morgan NguyenBehavior Technician1841124542
  18. Paul Nguyen, PT, DPTPhysical Therapist1508469339
  19. Quynh NguyenCase Manager/Care Coordinator1740747617
  20. Sophia NguyenBehavior Analyst1235637364
  21. Steve NguyenBehavior Technician1134682537
  22. Steven NguyenBehavior Analyst1699357061
  23. Tammy NguyenBehavior Analyst1386124360
  24. Tammy NguyenBehavior Analyst1770257313
  25. Tena NguyenBehavior Technician1548720857
  26. Thien Di Nguyen, D.C., B.S.Chiropractor1780865469
  27. Tina Nguyen, ODOptometrist1255942207
  28. Tracy NguyenBehavior Analyst1194374298
  29. Trang NguyenPharmacist1487153623
  30. Tu NguyenBehavior Technician1649091570
  31. Valerie Nguyen, PHARM DPharmacist1881148500
  32. Victor Nguyen, D.P.T.Physical Therapist1790296192
  33. Victoria Nguyen, PHARM.D.Pharmacist1164883153
  34. Vivi NguyenCase Manager/Care Coordinator1972901486
  35. Vivian NguyenBehavior Technician1689225401
  36. Cristian Nguyen GallardoBehavior Analyst1093527061
  37. Theresa Nguyenduc, DMDGeneral Practice Dentistry1982746921
  38. Carlene NhuBehavior Analyst1962290072
  39. Ryan Nichols, DCChiropractor1841899812
  40. Laney NicodemusBehavior Technician1144153644
  41. Christie NietoBehavior Technician1447882113
  42. Andrea NightingaleBehavior Analyst1316770589
  43. Adriana Niizawa, LMFTMarriage & Family Therapist1346549375
  44. Rita Nijjar, PA-CDermatology Physician1245306935
  45. Jila Nikkhah, DDSGeneral Practice Dentistry1780892083
  46. Kourosh Niknafs, DDSDentist1982762985
  47. Ken Nishiguchi, PHARM.D.Pharmacist1891187845
  48. Mandi NishimoriBehavior Technician1245909944
  49. Daniel No, DDSGeneral Practice Dentistry1730492133
  50. Jayden NoBehavior Analyst1578439600

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

Costa Mesa, California appears in the CMS National Plan and Provider Enumeration System with 4,286 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 Costa Mesa - 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 Costa Mesa 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 Costa Mesa is weighted toward Behavior Analyst (1,239 clinicians, followed by Behavior Technician with 909 and Marriage & Family Therapist with 219). 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, Costa Mesa reports roughly 11 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.

Of California's most common specialties, Internal Medicine Physician is the most prominent one with no provider currently listing a Costa Mesa practice address, a coverage gap Costa Mesa patients typically fill by traveling to a larger nearby hub.

For Costa Mesa 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 Costa Mesa, CA?

There are 4,286 registered healthcare providers in Costa Mesa, CA, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in Costa Mesa?

The most common specialties in Costa Mesa are Behavior Analyst, Behavior Technician, Marriage & Family Therapist, Physical Therapist, Chiropractor. Behavior Analyst has the most providers with 1,239.

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.