| Nurse practitioner | 6,963 |
| Physician assistant | 5,492 |
| Licensed clinical social worker | 3,907 |
| Internal medicine | 3,397 |
| Family practice | 3,298 |
| Physical therapist (private practice) | 3,061 |
| Certified Registered Nurse Anesthetist (CRNA) | 2,500 |
| Chiropractic | 1,835 |
| Emergency medicine | 1,817 |
| Mental Health Counselors | 1,355 |
| Anesthesiology | 1,139 |
| Obstetrics/gynecology | 1,131 |
| Optometrist | 1,125 |
| Clinical psychologist | 1,054 |
| Psychiatry | 980 |
| Diagnostic Radiology | 964 |
| Mass Immunization Roster Billers | 827 |
| General surgery | 728 |
| Orthopedic surgery | 689 |
| Cardiology | 632 |
| Ophthalmology | 604 |
| Podiatry | 596 |
| Neurology | 572 |
| Occupational therapist (private practice) | 544 |
| Pathology | 419 |
| Physical medicine and rehabilitation | 395 |
| Pediatric medicine | 387 |
| Gastroenterology | 378 |
| Pulmonary disease | 359 |
| Hospitalist | 349 |
| Dermatology | 344 |
| Urology | 304 |
| Otolaryngology | 288 |
| Audiologist (billing independently) | 274 |
| Hematology/oncology | 261 |
| Nephrology | 257 |
| Ambulance Service Supplier, e.g., private ambulance companies, funeral homes | 252 |
| Centralized Flu | 227 |
| Infectious disease | 215 |
| Neurosurgery | 183 |
| Endocrinology | 181 |
| Certified nurse midwife | 165 |
| Radiation oncology | 161 |
| Speech / language pathology | 160 |
| Interventional Cardiology | 138 |
| Rheumatology | 134 |
| Vascular surgery | 132 |
| Plastic and reconstructive surgery | 132 |
| Allergy/immunology | 130 |
| Pharmacy | 123 |
| Ambulatory Surgical Center | 122 |
| Critical care (intensivists) | 114 |
| Thoracic surgery | 104 |
| Interventional radiology | 96 |
| General practice | 95 |
| Medical oncology | 82 |
| Geriatric medicine | 77 |
| Pain Management | 73 |
| Cardiac Electrophysiology | 69 |
| Sports Medicine | 69 |
| Colorectal surgery (formerly proctology) | 69 |
| Maxillofacial surgery | 63 |
| Clinical Laboratory (Billing Independently) | 58 |
| Oral surgery (dentists only) | 54 |
| Hand surgery | 53 |
| Osteopathic manipulative therapy | 52 |
| Hospice and Palliative Care | 50 |
| Registered Dietician/Nutrition Professional | 49 |
| Opioid Treatment Program | 39 |
| Sleep Medicine | 38 |
| Hematology | 36 |
| Interventional Pain Management (IPM) | 36 |
| Anesthesiologist Assistant | 31 |
| Marriage and Family Therapist | 30 |
| Independent Diagnostic Testing Facility (IDTF) | 30 |
| Advanced Heart Failure and Transplant Cardiology | 26 |
| Cardiac surgery | 26 |
| Gynecologist/oncologist | 23 |
| Epileptologists | 22 |
| Surgical oncology | 21 |
| Addiction medicine | 20 |
| Certified clinical nurse specialist | 16 |
| Nuclear medicine | 14 |
| Micrographic Dermatologic Surgery | 13 |
| Preventive medicine | 11 |
| Medical Genetics and Genomics | 10 |
| Neuropsychiatry | 7 |
| Unknown Provider | 7 |
| Dentist | 6 |
| Home Infusion Therapy Services | 6 |
| Psychologist (billing independently) | 5 |
| Portable X-Ray Supplier (Billing Independently) | 5 |
| Medicare Diabetes Preventive Program | 4 |
| General Psychiatry | 4 |
| Hematopoietic Cell Transplantation and Cellular Therapy | 3 |
| Undersea and Hyperbaric Medicine | 2 |
| Oral and Maxillofacial Pathology | 2 |
| Radiation Therapy Centers | 2 |
| Adult Congenital Heart Disease | 2 |
| Unknown physician specialty | 1 |