Registry data as of Aug 27, 2026

Doctors and health care providers in O Fallon, IL

1,077 individual NPPES records list a O Fallon practice address, 44th of 541 Illinois cities. The largest group is behavior technician: 299, 28% of the city's records, against 4% across Illinois.

CMS NPPES registry, loaded Aug 27, 2026 · method · Verify with CMS →

The 8 largest groups in O Fallon

Source: CMS NPPES primary taxonomy, loaded Aug 27, 2026.

O Fallon in Illinois

  • Rank in Illinois44th of 541 cities by records
  • Share of the state0.4% of Illinois's records
  • Specialties present25 or more taxonomy codes
  • Top three groups39.2% of all records
  • Behavior Technician rank4th of the 10 Illinois cities with the most

Compared with Illinois as a whole, O Fallon has 6.9× the state's share of behavior technician records and 0.26× its share of internal medicine physician records.

Providers in O Fallon, alphabetically

  1. Alexis AaronBehavior Technician1831036003
  2. Megan Abrahamian, RBTBehavior Technician1619432945
  3. Ramontay AbramBehavior Technician1891621439
  4. Oluwadamilola Adegbenro, M.DStudent in an Organized Health Care Education/Training Program1629872601
  5. Eyasu AdunaStudent in an Organized Health Care Education/Training Program1548062532
  6. Emilio Aguinaldo, M.D.Student in an Organized Health Care Education/Training Program1184412959
  7. Esha Ahirwar, M.D.Student in an Organized Health Care Education/Training Program1609711217
  8. Fatima Ahmad, M.D.Student in an Organized Health Care Education/Training Program1659217214
  9. Oreoluwa AkinsolaStudent in an Organized Health Care Education/Training Program1285573113
  10. Ashraf Al Dadah, MDCardiovascular Disease Physician1457526576
  11. Roula Al-Dahhak, M.D.Neurology Physician1033116165
  12. Rebecca Albaugh, CCC-SLPSpeech-Language Pathologist1235656646
  13. Morgan AlbersBehavior Technician1871171181
  14. Nicole Albers, PHARMDPharmacist1720683337
  15. Victoria AllenBehavior Technician1467952838
  16. Caitlin AlonzoNurse Practitioner1083576243
  17. Rebecca AlthoffPediatric Occupational Therapist1942130687
  18. Ashley Amburn, LCPCMental Health Counselor1043672512
  19. Akossiwa Amenyo, HAIR LOSS SPECIALISTProsthetics Case Management1669029096
  20. Ronald Ames, DMDGeneral Practice Dentistry1235306994
  21. Candace AmesquitaBehavior Technician1841835733
  22. Nicole Amos, PTPhysical Therapist1326112988
  23. Christopher Anderson, DPMFoot Surgery Podiatrist1790760494
  24. Hallie AndersonBehavior Technician1780335281
  25. Stephanie AndersonBehavior Analyst1508468216
  26. Jessica AndrewsBehavior Technician1861072241
  27. Tyler AndrewsHearing Instrument Specialist1962807289
  28. Chelsea AngleBehavior Technician1316583305
  29. Venkatesh Anjan, M.D.Cardiovascular Disease Physician1275799850
  30. Mackenzie ArchamboBehavior Analyst1245702869
  31. Gerogina ArenasBehavior Technician1730077314
  32. Stephanie Armstrong, PA-CPhysician Assistant1962700757
  33. Brooke Arnel, RBTBehavior Technician1770129769
  34. Brittany ArthurProfessional Counselor1649730706
  35. Tatum AsbeckBehavior Technician1710642525
  36. Jayden AshfordBehavior Technician1467274035
  37. Bassim Assioun, M.D.Student in an Organized Health Care Education/Training Program1669785408
  38. Alan AzarEndodontics1659416212
  39. Karlee Bachmann, BCBABehavior Analyst1518569326
  40. Justin Baecht, CRNACertified Registered Nurse Anesthetist1801034491
  41. Leah Baecht, DNP, CRNA, APRNCertified Registered Nurse Anesthetist1275831273
  42. Scott Baer, LCSWClinical Social Worker1639363229
  43. David Bailey, DOStudent in an Organized Health Care Education/Training Program1730870635
  44. Saba Bajwa, MDStudent in an Organized Health Care Education/Training Program1487113478
  45. Makayla BakerBehavior Analyst1114587284
  46. Andrea BakosBehavior Technician1063244507
  47. Laura Baltz, SCHOOL PSYCHOLOGISTSchool Psychologist1134665110
  48. Lawrence Barnes, PA-CMedical Physician Assistant1184685174
  49. Taylor BarnesBehavior Technician1386204501
  50. Chelsey BarrettHearing Instrument Specialist1962226530

The largest Illinois cities

  1. Chicago63,379
  2. Springfield4,997
  3. Naperville4,634
  4. Peoria4,621
  5. Evanston4,013

All of Illinois →

How to read this directory

O Fallon, Illinois appears in the CMS National Plan and Provider Enumeration System with 1,077 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 O Fallon - 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 O Fallon 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 O Fallon is weighted toward Behavior Technician (299 clinicians, followed by Speech-Language Pathologist with 68 and Student in an Organized Health Care Education/Training Program with 55). 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 Illinois's population, O Fallon reports roughly 8.6 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 Illinois's most common specialties, Social Worker is the most prominent one with no provider currently listing a O Fallon practice address, a coverage gap O Fallon patients typically fill by traveling to a larger nearby hub.

For O Fallon 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 O Fallon, IL?

There are 1,077 registered healthcare providers in O Fallon, IL, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in O Fallon?

The most common specialties in O Fallon are Behavior Technician, Speech-Language Pathologist, Student in an Organized Health Care Education/Training Program, Family Medicine Physician, Behavior Analyst. Behavior Technician has the most providers with 299.

Source: CMS National Plan and Provider Enumeration System (NPPES), file loaded Aug 27, 2026 (NPPES files on CMS.gov). Records are self-reported registrations, not licenses.

Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.