NPPES file of Aug 9, 2026

Doctors and health care providers in Monrovia, CA

17,347 individual NPPES records list a practice address in Monrovia, 8th of 812 California cities. The largest group is behavior technician: 16,526, 95% of the city's records, against 18% across California. Page 54 of 347.

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

The 8 largest groups in Monrovia

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

Monrovia in California

  • Rank in California8th of 812 cities by records
  • Share of the state1.8% of California's records
  • Specialties present25 or more taxonomy codes
  • Top three groups96.4% of all records
  • Behavior Technician rank1st of the 10 California cities with the most

Compared with California as a whole, Monrovia has 5.4× the state's share of behavior technician records and 0.09× its share of marriage & family therapist records.

Providers in Monrovia, alphabetically

  1. Kenia CastilloBehavior Technician1528919503
  2. Lesley CastilloBehavior Technician1689381410
  3. Luna CastilloBehavior Technician1124842232
  4. Maria CastilloBehavior Technician1407739451
  5. Richard CastilloBehavior Technician1174445563
  6. Ruby CastilloBehavior Technician1407534167
  7. Teresa CastilloBehavior Technician1063269918
  8. Thomas CastilloBehavior Technician1790537637
  9. Whitney CastilloBehavior Technician1144039017
  10. Wilfredo CastilloBehavior Technician1336827534
  11. Zunhaila CastilloBehavior Technician1538927033
  12. Jose Castillo De SerinBehavior Analyst1992338685
  13. Leyla Castillo GalvezBehavior Technician1306626742
  14. Blanca Estrella Castillo GuzmanBehavior Technician1134807399
  15. Ciara Lyn Castillo-GonzalezBehavior Technician1821732140
  16. Mariana CastleBehavior Technician1437916202
  17. Adrienna CastoroBehavior Technician1194558197
  18. Alexis CastroBehavior Technician1659123594
  19. Alyssa CastroBehavior Technician1568118560
  20. Amber Castro, MAMarriage & Family Therapist1194384412
  21. Andrea CastroBehavior Technician1295424448
  22. Arthur CastroBehavior Technician1497587216
  23. Berenice CastroBehavior Technician1083453088
  24. Brenda CastroBehavior Technician1801784418
  25. Brian CastroBehavior Technician1922929884
  26. Clarisa CastroBehavior Technician1053115311
  27. Elizabeth CastroBehavior Technician1598608606
  28. Jasmine CastroBehavior Technician1518840560
  29. Jasmine CastroBehavior Technician1013865971
  30. Jessica CastroBehavior Technician1508587510
  31. Leslie CastroBehavior Technician1356063713
  32. Litzy CastroBehavior Technician1508780925
  33. Marissa CastroBehavior Technician1811724966
  34. Maya CastroBehavior Technician1427745587
  35. Priscila CastroBehavior Technician1699502294
  36. Richard CastroBehavior Technician1861313801
  37. Samantha CastroBehavior Technician1053123224
  38. Saray CastroBehavior Technician1073238937
  39. Shania CastroBehavior Technician1023865599
  40. Mia Castro McGeeBehavior Technician1962340869
  41. Elsa Castro-GarciaBehavior Technician1689491292
  42. Faithallianne CatacutanBehavior Technician1013838978
  43. Ashley CatanoBehavior Technician1336727437
  44. Theresa CatheyBehavior Technician1477444065
  45. Christine CaudilloBehavior Technician1811730534
  46. Megan CaudilloOccupational Therapy Assistant1376259192
  47. Alexis CavadaBehavior Technician1033969464
  48. Katelyn CavalieriBehavior Technician1982318143
  49. Brianna CavanaghBehavior Technician1437974292
  50. Ivonne Cavanaugh ReyesBehavior Technician1447085196

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

Monrovia, California appears in the CMS National Plan and Provider Enumeration System with 17,347 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 Monrovia - 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 Monrovia 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 Monrovia is weighted toward Behavior Technician (16,526 clinicians, followed by Behavior Analyst with 109 and Marriage & Family Therapist with 94). 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, Monrovia reports roughly 44.5 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, Addiction (Substance Use Disorder) Counselor is the most prominent one with no provider currently listing a Monrovia practice address, a coverage gap Monrovia patients typically fill by traveling to a larger nearby hub.

For Monrovia 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 Monrovia, CA?

There are 17,347 registered healthcare providers in Monrovia, CA, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in Monrovia?

The most common specialties in Monrovia are Behavior Technician, Behavior Analyst, Marriage & Family Therapist, Speech-Language Pathologist, Student in an Organized Health Care Education/Training Program. Behavior Technician has the most providers with 16,526.

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.