| Nurse practitioner | 451 |
| Physician assistant | 251 |
| Licensed clinical social worker | 218 |
| Family practice | 195 |
| Mental Health Counselors | 187 |
| Physical therapist (private practice) | 184 |
| Internal medicine | 170 |
| Emergency medicine | 99 |
| Clinical psychologist | 93 |
| Chiropractic | 85 |
| Psychiatry | 84 |
| Diagnostic Radiology | 76 |
| Anesthesiology | 71 |
| Optometrist | 57 |
| Certified Registered Nurse Anesthetist (CRNA) | 57 |
| Mass Immunization Roster Billers | 54 |
| Obstetrics/gynecology | 47 |
| General surgery | 43 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 37 |
| Neurology | 34 |
| Cardiology | 33 |
| Pathology | 32 |
| Orthopedic surgery | 31 |
| Ophthalmology | 25 |
| Hospitalist | 24 |
| Registered Dietician/Nutrition Professional | 21 |
| Pulmonary disease | 19 |
| Gastroenterology | 19 |
| Audiologist (billing independently) | 18 |
| Pediatric medicine | 17 |
| Hematology/oncology | 17 |
| Podiatry | 17 |
| Dermatology | 16 |
| Urology | 15 |
| Infectious disease | 14 |
| Marriage and Family Therapist | 14 |
| Anesthesiologist Assistant | 14 |
| Centralized Flu | 13 |
| Certified nurse midwife | 13 |
| Medical oncology | 12 |
| Hospice and Palliative Care | 12 |
| Critical care (intensivists) | 12 |
| Otolaryngology | 10 |
| Radiation oncology | 10 |
| Nephrology | 9 |
| Physical medicine and rehabilitation | 8 |
| Occupational therapist (private practice) | 7 |
| Interventional radiology | 7 |
| Endocrinology | 7 |
| Speech / language pathology | 7 |
| Geriatric medicine | 6 |
| Cardiac Electrophysiology | 6 |
| Rheumatology | 6 |
| Opioid Treatment Program | 5 |
| Vascular surgery | 5 |
| Pharmacy | 4 |
| Plastic and reconstructive surgery | 4 |
| Osteopathic manipulative therapy | 4 |
| Interventional Cardiology | 4 |
| Pain Management | 3 |
| Allergy/immunology | 3 |
| Sports Medicine | 3 |
| Neurosurgery | 3 |
| Colorectal surgery (formerly proctology) | 3 |
| Addiction medicine | 3 |
| Hematology | 3 |
| Certified clinical nurse specialist | 3 |
| Gynecologist/oncologist | 2 |
| Clinical Laboratory (Billing Independently) | 2 |
| Independent Diagnostic Testing Facility (IDTF) | 2 |
| Oral surgery (dentists only) | 2 |
| Sleep Medicine | 2 |
| General practice | 2 |
| Preventive medicine | 2 |
| Maxillofacial surgery | 1 |
| Single or Multispecialty Clinic or Group Practice | 1 |
| Epileptologists | 1 |
| Thoracic surgery | 1 |
| Medical Genetics and Genomics | 1 |
| Ambulatory Surgical Center | 1 |
| Surgical oncology | 1 |
| Hand surgery | 1 |