NPPES file of Aug 9, 2026

Doctors and health care providers in O Fallon, IL

1,077 individual NPPES records list a practice address in O Fallon, 44th of 541 Illinois cities. The largest group is behavior technician: 295, 27% of the city's records, against 4% across Illinois. Page 10 of 22.

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

The 8 largest groups in O Fallon

Source: CMS NPPES primary taxonomy, file of Aug 9, 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 groups37.7% of all records
  • Behavior Technician rank4th of the 10 Illinois cities with the most

Compared with Illinois as a whole, O Fallon has 7× the state's share of behavior technician records and 0.25× its share of mental health counselor records.

Providers in O Fallon, alphabetically

  1. Anne JenkinsLow-Risk Neonatal Registered Nurse1346097359
  2. Jacora JenkinsBehavior Technician1467120279
  3. Mackenzie JerlsBehavior Technician1477237352
  4. Jason Jerome, PH.D., M.D.Emergency Medicine Physician1881055762
  5. Crystal Jesenick, A.N.P.-CAdult Health Nurse Practitioner1396831616
  6. Donna Jewell, PHD, RN, FNP-BCFamily Nurse Practitioner1649626144
  7. Stephen Johans, M.D.Neurological Surgery Physician1013273580
  8. Chloe Johansson, RBTBehavior Technician1013772318
  9. Amanda JohnsonSpeech-Language Pathologist1154642148
  10. Stefanie Johnson, LCPCProfessional Counselor1871821074
  11. William Johnson, RPHPharmacotherapy Pharmacist1740647767
  12. Kedriunna Johnson FrenchBehavior Technician1649192428
  13. Phillis Johnson-Haywood, LPCProfessional Counselor1699343749
  14. Dakota Johnston, BEHAVIORAL TECHBehavior Technician1861221566
  15. Amanda JondroBehavior Technician1770197667
  16. Chania JonesBehavior Technician1639006547
  17. Cody Jones, DCChiropractor1770131195
  18. Dainese Jones, CRC, LCPCCounselor1205694510
  19. Katherine Jones, APRNNurse Practitioner1972229987
  20. Stephen Jubinski, M.D.Family Medicine Physician1932377249
  21. Margaret JudsonSpeech-Language Pathologist1184801763
  22. Christianne Judy, MSW, LCSWClinical Social Worker1023186806
  23. Ellie Junker, RBTBehavior Technician1255953451
  24. Kris KahlerVascular & Interventional Radiology Physician1205300795
  25. Lucas KaliszakStudent in an Organized Health Care Education/Training Program1427900034
  26. Amy Katsikas, CNSClinical Nurse Specialist1932728169
  27. Gurleen KaurBehavior Technician1447959283
  28. Allison KeilbachBehavior Technician1871379768
  29. Meagan Kennedy, DPTPhysical Therapist1700125903
  30. Jamie Kilquist, PTAPhysical Therapy Assistant1275101446
  31. Kathy Kinder, NCMTMechanotherapist1134451834
  32. Travis King, PTA, LMTPhysical Therapy Assistant1023837085
  33. Danika Kingsley, PHARM.DPharmacist1053932285
  34. Mary Kinkelaar, RBTBehavior Technician1578346433
  35. Dannette KinsellaDevelopmental Therapist1497023055
  36. Tracie Kloeppel, CRNACertified Registered Nurse Anesthetist1952792665
  37. Vivian Kloke, ODOptometrist1346358645
  38. Megan Knetzer, FNPAdult Health Nurse Practitioner1790301232
  39. Richard Knight, MSN FNP-BCFamily Nurse Practitioner1992959282
  40. Laura Knuf, PHARM.D.Pharmacist1871079517
  41. Kelsey Koenig, PA-CPhysician Assistant1962973982
  42. Miranda Koesterer, OTR/LOccupational Therapist1659909950
  43. Haley Kohnen, PTAPhysical Therapy Assistant1912756065
  44. Torre Kohrmann, RBTBehavior Technician1467098319
  45. Pawelle KoleBehavior Technician1053163055
  46. Caitlyn KoloBehavior Technician1326510660
  47. Greg Komeshak, D.C.Chiropractor1265502611
  48. Rachel Komeshak, PTPhysical Therapist1821112640
  49. Mallory Kovarik, PHARMDPharmacist1649870874
  50. Annabelle KowalskiBehavior Technician1780405720

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 (295 clinicians, followed by Speech-Language Pathologist with 67 and Family Medicine Physician with 44). 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, Internal Medicine Physician 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, Family Medicine Physician, Student in an Organized Health Care Education/Training Program, Behavior Analyst. Behavior Technician has the most providers with 295.

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.