NPPES file of Aug 9, 2026

Doctors and health care providers in Boulder, CO

5,635 individual NPPES records list a practice address in Boulder, 5th of 193 Colorado cities. The largest group is mental health counselor: 1,009, 18% of the city's records, against 6% across Colorado. Page 94 of 113.

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

The 8 largest groups in Boulder

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

Boulder in Colorado

  • Rank in Colorado5th of 193 cities by records
  • Share of the state3.8% of Colorado's records
  • Specialties present25 or more taxonomy codes
  • Top three groups29.4% of all records
  • Mental Health Counselor rank2nd of the 10 Colorado cities with the most

Compared with Colorado as a whole, Boulder has 3.9× the state's share of acupuncturist records and 0.47× its share of behavior technician records.

Providers in Boulder, alphabetically

  1. Lonnie Sibley, DDSOral and Maxillofacial Surgery (Dentist)1033287115
  2. Paul Sica, D.M.D.General Practice Dentistry1750470217
  3. Molly Sicard, ATCAthletic Trainer1164913331
  4. Jeffrey SiddersMental Health Counselor1669762118
  5. Lodi SieferProfessional Counselor1467698688
  6. Evan SiegelBehavior Technician1487430054
  7. Stephen Siegel, M. D.Urology Physician1902860091
  8. Jill Siegfried, M.D.Family Medicine Physician1013991611
  9. Arthur Siegle, RPHPharmacist1164556148
  10. Kelly Sikora, LPCMental Health Counselor1396512604
  11. Benjamin SilverAddiction (Substance Use Disorder) Counselor1043618820
  12. David Silver, MD, MPHEmergency Medicine Physician1194973305
  13. Nicole Silver, MDInternal Medicine Physician1184642209
  14. Joel Silverman, M.A., L.P.C.Professional Counselor1275667214
  15. Robert Simeral, DDSDentist1730271172
  16. Adrianna Simmons, PT, DPTPhysical Therapist1619717212
  17. Ashley SimmonsMassage Therapist1053546374
  18. Kristina Simmons RossClinical Social Worker1538758859
  19. Emily Simon, MCD, CCC-SLPSpeech-Language Pathologist1063284636
  20. Rebecca Simone, LPCCMental Health Counselor1467174037
  21. Susan Simone, PTPhysical Therapist1912177593
  22. Andrea SimonsPharmacist1699363895
  23. David Simons, M.D.Family Medicine Physician1801879499
  24. Suzanne Simons, P.T.Specialist1083825749
  25. Jennifer Simonson, OD, FOVDR, FAAOVision Therapy Optometrist1184624520
  26. Lynzee Simpson, DCChiropractor1003762147
  27. Thomas Simpson, D.D.S.General Practice Dentistry1568573095
  28. Ashley Simpson Shires, LPCMental Health Counselor1881450237
  29. Colleen SinclairMental Health Counselor1700275708
  30. Lauren Sinclair, LPCProfessional Counselor1952952764
  31. Melissa SinclairBehavior Technician1235801432
  32. Simone Sine, MAMental Health Counselor1912734039
  33. Dawn Singleton, PTOrthopedic Physical Therapist1245323906
  34. Ishika SinhaBehavior Technician1912721986
  35. Colin Sink, PT, DPTPhysical Therapist1215868476
  36. Tolley Sink, L.AC., DIPL. OMAcupuncturist1952688624
  37. Carly SinnMental Health Counselor1003734583
  38. Celia Sinoway, PH.D.Psychologist1235149683
  39. Jessika Siorai, LACAcupuncturist1457474116
  40. Mark Sipowicz, REGISTERED THERAPISTMental Health Counselor1205480845
  41. Ann Sirotniak, PTPhysical Therapist1346469236
  42. Kaitlin Sisk, DVMSpecialist1336746643
  43. Mark Sitarik, MDHematology & Oncology Physician1346224664
  44. Abigail SjostromMental Health Counselor1114279494
  45. Deborah Skarda, MDInternal Medicine Physician1457488413
  46. Jodi Sklawer, M.S., CCC-SLPSpeech-Language Pathologist1700037249
  47. Allan Skromme, D.D.S.General Practice Dentistry1396813382
  48. Carl Skulski, DDSEndodontics1689649196
  49. Brandon SladeMental Health Counselor1700118502
  50. Ayala SlaterPhysical Medicine & Rehabilitation Physician1528520319

The largest Colorado cities

  1. Denver25,068
  2. Colorado Springs19,771
  3. Aurora17,400
  4. Fort Collins6,928
  5. Lakewood4,944

All of Colorado →

How to read this directory

Boulder, Colorado appears in the CMS National Plan and Provider Enumeration System with 5,635 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 Boulder - 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 Boulder 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 Boulder is weighted toward Mental Health Counselor (1,009 clinicians, followed by Professional Counselor with 334 and Clinical Social Worker with 316). 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 Colorado's population, Boulder reports roughly 95.9 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 Colorado's most common specialties, Student in an Organized Health Care Education/Training Program is the most prominent one with no provider currently listing a Boulder practice address, a coverage gap Boulder patients typically fill by traveling to a larger nearby hub.

For Boulder 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 Boulder, CO?

There are 5,635 registered healthcare providers in Boulder, CO, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in Boulder?

The most common specialties in Boulder are Mental Health Counselor, Professional Counselor, Clinical Social Worker, Physical Therapist, Behavior Technician. Mental Health Counselor has the most providers with 1,009.

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.