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 5 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. Nicole Cox, RBTBehavior Technician1811683006
  2. Lauren CraftBehavior Technician1659889467
  3. Jami Craig, LCSWClinical Social Worker1174179873
  4. Crista Crawford, SLPSpeech-Language Pathologist1144491796
  5. Jennifer Cripps, CRNACertified Registered Nurse Anesthetist1104177724
  6. Angela Croessman-Marshall, AGNP-CAdult Health Nurse Practitioner1023994274
  7. Victoria CroissantBehavior Technician1760358816
  8. Anita Crooks, RNRegistered Nurse1093968109
  9. Danielle CrouchBehavior Technician1356222806
  10. Kendyl CuddiheeBehavior Technician1689165870
  11. Shambra Cullum, APNFamily Nurse Practitioner1033615463
  12. Maria Cunningham, LPTPain Medicine (Physical Medicine & Rehabilitation) Physician1881979623
  13. Christian Czech, FNP-CFamily Nurse Practitioner1366372500
  14. Dominique D'Souza, MDFamily Medicine Physician1861078206
  15. Josef DabrowskiBehavior Technician1811405780
  16. Maurice DaleEmergency Medicine Physician1639757958
  17. Nicholas Dane, BEHAVIOR TECHNICIANBehavior Technician1043070493
  18. Jessica Daniel, OTD, OTR/LOccupational Therapist1669293692
  19. Brandon Daniels, DCChiropractor1992203491
  20. Tess DavidBehavior Technician1043880032
  21. Alex DavieCertified Registered Nurse Anesthetist1912599085
  22. John DavisRegistered Nurse1396174751
  23. Leslie Davis, MA,LCPCCounselor1255856282
  24. Morgan Delozier, DOFamily Medicine Physician1801537840
  25. Rachael Demattei, APRNNurse Practitioner1891443289
  26. Richard Derby, MDSports Medicine (Family Medicine) Physician1295720845
  27. Jennifer Deschene, LMTMassage Therapist1962087593
  28. Rajeev Dewan, M.D.Geriatric Medicine (Internal Medicine) Physician1699806638
  29. Jennifer DialBehavior Technician1295357960
  30. Andrew Dichsen, OTR/LOccupational Therapist1134836786
  31. Kristi Dieckmann, D.C., M.S.Rehabilitation Chiropractor1720309768
  32. Jamie Diekemper, RBTBehavior Technician1487299640
  33. Kelly DiekemperSpeech-Language Pathologist1285992560
  34. Amanda Dillard, LCPC, NCCProfessional Counselor1619590767
  35. Angela DillickNurse's Aide1609344423
  36. Katherine Dillon, LCSWClinical Social Worker1528472974
  37. Danielle DitterlineBehavior Technician1598370843
  38. Elizabeth DivineBehavior Technician1003525940
  39. Sarah DixonBehavior Technician1750903456
  40. Angie DolosicSchool Psychologist1043809825
  41. Gwen DonleyProfessional Counselor1528811015
  42. Randall Dooley, MDUrology Physician1619940640
  43. Christina Dothager, M.D.Obstetrics & Gynecology Physician1508067596
  44. Jakia DouglasBehavior Technician1740752369
  45. Mara Downing, MDStudent in an Organized Health Care Education/Training Program1003756461
  46. Susan Drabing, FNP-BCFamily Nurse Practitioner1326345141
  47. Dawn Drewes, APNFamily Nurse Practitioner1700177763
  48. Vincent Duenas, MDHospitalist Physician1083142152
  49. Victoria DunaheeBehavior Analyst1427627264
  50. Ella Duncan, LCSWClinical Social Worker1386620375

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.