| Nurse practitioner | 1,652 |
| Physician assistant | 1,392 |
| Physical therapist (private practice) | 1,154 |
| Licensed clinical social worker | 1,021 |
| Internal medicine | 909 |
| Family practice | 842 |
| Certified Registered Nurse Anesthetist (CRNA) | 839 |
| Chiropractic | 560 |
| Mental Health Counselors | 398 |
| Emergency medicine | 378 |
| Obstetrics/gynecology | 335 |
| Clinical psychologist | 312 |
| Anesthesiology | 295 |
| Diagnostic Radiology | 289 |
| Optometrist | 267 |
| Mass Immunization Roster Billers | 262 |
| Psychiatry | 231 |
| Orthopedic surgery | 227 |
| Ophthalmology | 217 |
| Podiatry | 214 |
| Cardiology | 187 |
| General surgery | 174 |
| Neurology | 166 |
| Occupational therapist (private practice) | 161 |
| Dermatology | 139 |
| Pathology | 123 |
| Physical medicine and rehabilitation | 115 |
| Gastroenterology | 104 |
| Urology | 101 |
| Pulmonary disease | 101 |
| Otolaryngology | 100 |
| Hospitalist | 87 |
| Nephrology | 78 |
| Hematology/oncology | 74 |
| Infectious disease | 73 |
| Pediatric medicine | 70 |
| Audiologist (billing independently) | 66 |
| Centralized Flu | 59 |
| Endocrinology | 59 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 53 |
| Radiation oncology | 51 |
| Speech / language pathology | 50 |
| Neurosurgery | 49 |
| Ambulatory Surgical Center | 48 |
| Allergy/immunology | 47 |
| Interventional Cardiology | 45 |
| Pharmacy | 42 |
| Rheumatology | 42 |
| Plastic and reconstructive surgery | 40 |
| Maxillofacial surgery | 31 |
| Certified nurse midwife | 31 |
| Medical oncology | 30 |
| Vascular surgery | 30 |
| Interventional radiology | 26 |
| Oral surgery (dentists only) | 26 |
| Thoracic surgery | 25 |
| Pain Management | 25 |
| General practice | 22 |
| Sports Medicine | 22 |
| Colorectal surgery (formerly proctology) | 22 |
| Cardiac Electrophysiology | 18 |
| Clinical Laboratory (Billing Independently) | 17 |
| Registered Dietician/Nutrition Professional | 16 |
| Hand surgery | 14 |
| Critical care (intensivists) | 13 |
| Geriatric medicine | 12 |
| Opioid Treatment Program | 11 |
| Interventional Pain Management (IPM) | 10 |
| Osteopathic manipulative therapy | 9 |
| Sleep Medicine | 9 |
| Independent Diagnostic Testing Facility (IDTF) | 9 |
| Marriage and Family Therapist | 8 |
| Cardiac surgery | 8 |
| Gynecologist/oncologist | 8 |
| Hematology | 7 |
| Epileptologists | 7 |
| Surgical oncology | 5 |
| Certified clinical nurse specialist | 4 |
| Hospice and Palliative Care | 4 |
| Nuclear medicine | 4 |
| Micrographic Dermatologic Surgery | 4 |
| Preventive medicine | 3 |
| Neuropsychiatry | 2 |
| Oral and Maxillofacial Pathology | 2 |
| Home Infusion Therapy Services | 2 |
| Dentist | 2 |
| Medical Genetics and Genomics | 2 |
| Advanced Heart Failure and Transplant Cardiology | 2 |
| Medicare Diabetes Preventive Program | 1 |
| Undersea and Hyperbaric Medicine | 1 |
| Unknown Provider | 1 |
| Addiction medicine | 1 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 1 |
| Anesthesiologist Assistant | 1 |