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 17 of 22.

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

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

The 8 largest groups in O Fallon

  1. Behavior Technician295
  2. Speech-Language Pathologist67
  3. Family Medicine Physician44
  4. Students in training43
  5. Behavior Analyst43
  6. Chiropractor35
  7. Family Nurse Practitioner32
  8. Pharmacist31

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. Rebecca Riepshoff, PA-CPhysician Assistant1497754634
  2. Shauna Rittenhouse, OTR/LPediatric Occupational Therapist1043618200
  3. Celia RoarkBehavior Technician1164037917
  4. Kenneth Roberts, MA, RD, LDNRegistered Dietitian1124678578
  5. Jessica Rodriguez, M.S. CCC-SLPSpeech-Language Pathologist1356751036
  6. Lunalis RodriguezBehavior Technician1437092855
  7. Samantha Rogers, RBTBehavior Technician1144059957
  8. Savannah RomanBehavior Technician1811561780
  9. William Rook, M.A., LCPCMental Health Counselor1194736397
  10. Elaina RossmanBehavior Technician1306542709
  11. Caroline Roti, DMDDentist1245073360
  12. Parker Roustio, DMDGeneral Practice Dentistry1841976842
  13. Scott Roustio, MDEmergency Medicine Physician1215080395
  14. Stephanie Roxby, LCSWClinical Social Worker1619761780
  15. Andrea Russell, MS, CCC-SLPSpeech-Language Pathologist1619115557
  16. Laine RussellBehavior Technician1215891106
  17. Renee Rutherford, PA-CPhysician Assistant1619166345
  18. Abbey SabaBehavior Technician1700431384
  19. Gabriella Sabatino, DCChiropractor1447552476
  20. Robinder Sahi, M.D.Hospitalist Physician1386200657
  21. Rachel Salazar, LCSWClinical Social Worker1033507652
  22. Sarah SalzmanAssistant Behavior Analyst1215498225
  23. Rema Sanghavi, D.O.Family Medicine Physician1104991017
  24. Halee SantiagoBehavior Technician1699620534
  25. Asia SatoOccupational Therapist1194560623
  26. Kirk Satrom, D.D.S., M.S.Orthodontics and Dentofacial Orthopedics Dentistry1386788768
  27. Shiyam Satwani, M.DInterventional Cardiology Physician1407067184
  28. Katherine SaundersBehavior Technician1487485371
  29. John Scally, MDCardiovascular Disease Physician1508952318
  30. Carmin Schadowsky, PTAPhysical Therapy Assistant1093536492
  31. Jennifer Schaefer, APNFamily Nurse Practitioner1396294153
  32. Samantha Schaub, BEHAVIOR TECHNICIANBehavior Technician1093529927
  33. Jennifer Schenck, PMHNP, RNPsychiatric/Mental Health Nurse Practitioner1184605834
  34. Lauren Schiefer, M.A., CCC-SLP/LStudent in an Organized Health Care Education/Training Program1598313942
  35. Margret Schierberl, MA, CCC-SLP/LSpeech-Language Pathologist1124559125
  36. Alex Schillinger, DMDDentist1629185814
  37. Lauren Schleyhahn, PHARMDPharmacist1790509057
  38. Madeleine SchlimmeBehavior Technician1306679865
  39. Gladys Schmees, FNPFamily Nurse Practitioner1679939516
  40. Amanda Schmitt, ACNPNurse Practitioner1912361411
  41. Danielle Schoenbacher, MS, ATC, LATC, PESAthletic Trainer1861126856
  42. Carmen Schott, LCSW, LISWClinical Social Worker1134365182
  43. Kara Schreder, D.M.D.General Practice Dentistry1285788356
  44. Stacy SchreiberPhysical Therapist1407255771
  45. Margaret Schuch, CRNACertified Registered Nurse Anesthetist1932247707
  46. Edward Schuessler, M.D.Anesthesiology Physician1811976707
  47. Dale Schutte, D.D.SDentist1659431500
  48. Halle SchwalenbergBehavior Technician1710712096
  49. Skylar SchwertnerStudent in an Organized Health Care Education/Training Program1205727492
  50. Christine Scott, RBTBehavior Technician1871139725

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.