| Coding | Meaning |
| 990 | Not treatment functions |
| & | Not known |
| 100 | General surgery |
| 101 | Urology |
| 102 | Transplantation surgery |
| 103 | Breast surgery |
| 104 | Colorectal surgery |
| 105 | Hepatobiliary & pancreatic surgery |
| 106 | Upper gastrointestinal surgery |
| 107 | Vascular surgery |
| 108 | Spinal surgery service |
| 110 | Trauma & orthopaedics |
| 120 | Ear, nose and throat (ENT) |
| 130 | Ophthalmology |
| 140 | Oral surgery |
| 141 | Restorative dentistry |
| 142 | Paediatric dentistry |
| 143 | Orthodontics |
| 144 | Maxillo-facial surgery |
| 150 | Neurosurgery |
| 160 | Plastic surgery |
| 161 | Burns care |
| 170 | Cardiothoracic surgery |
| 171 | Paediatric surgery |
| 172 | Cardiac surgery |
| 173 | Thoracic surgery |
| 174 | Cardiothoracic transplantation |
| 180 | Accident & emergency (A&E) |
| 190 | Anaesthetics [Until 31 March 2004] |
| 191 | Pain management |
| 192 | Critical care medicine |
| 199 | Non-UK Provider |
| 211 | Paediatric Urology |
| 212 | Paediatric Transplantation Surgery |
| 213 | Paediatric Gastrointestinal Surgery |
| 214 | Paediatric Trauma and Orthopaedics |
| 215 | Paediatric Ear Nose and Throat |
| 216 | Paediatric Ophthalmology |
| 217 | Paediatric Maxillo-Facial Surgery |
| 218 | Paediatric Neurosurgery |
| 219 | Paediatric Plastic Surgery |
| 220 | Paediatric Burns Care |
| 221 | Paediatric Cardiac Surgery |
| 222 | Paediatric Thoracic Surgery |
| 223 | Paediatric epilepsy |
| 241 | Paediatric Pain Management |
| 242 | Paediatric Intensive Care |
| 251 | Paediatric Gastroenterology |
| 252 | Paediatric Endocrinology |
| 253 | Paediatric Clinical Haematology |
| 254 | Paediatric Audiological Medicine |
| 255 | Paediatric Clinical Immunology and Allergy |
| 256 | Paediatric Infectious diseases |
| 257 | Paediatric Dermatology |
| 258 | Paediatric Respiratory Medicine |
| 259 | Paediatric Nephrology |
| 260 | Paediatric Medical Oncology |
| 261 | Paediatric Metabolic disease |
| 262 | Paediatric Pheumalogy |
| 263 | Paediatric diabetic medicine |
| 264 | Paediatric cystic fibrosis |
| 280 | Paediatric Interventional Radiology |
| 290 | Community Paediatrics |
| 291 | Paediatric Neuro-disability |
| 300 | General medicine |
| 301 | Gastroenterology |
| 302 | Endocrinology |
| 303 | Clinical haematology |
| 304 | Clinical Physiology |
| 305 | Clinical pharmacology |
| 306 | Hepatology |
| 307 | Diabetic medicine |
| 308 | Bone and marrow transplantation |
| 309 | Haemophilia |
| 310 | Audiological medicine |
| 311 | Clinical genetics |
| 312 | Clinical cytogenics and molecular genetics [Until 31 March 2004] |
| 313 | Clinical immunology and allergy |
| 314 | Rehabilitation |
| 315 | Palliative medicine |
| 316 | Clinical immunology |
| 317 | Allergy |
| 318 | Intermediate care |
| 319 | Respite care |
| 320 | Cardiology |
| 321 | Paediatric cardiology |
| 322 | Clinical microbiology |
| 323 | Spinal Injuries |
| 324 | Anticoagulant service |
| 325 | Sport and exercise medicine |
| 327 | Cardiac rehabilitation |
| 328 | Stroke medicine |
| 329 | Transient ischaemic attack |
| 330 | Dermatology |
| 331 | Congenital heart disease service |
| 340 | Thoracic medicine |
| 341 | Respiratory Physiology |
| 342 | Programmed pulmonary rehabilitation |
| 343 | Adult cystic fibrosis service |
| 344 | Complex specialised rehabilitation service |
| 345 | Specialist rehabilitation service |
| 346 | Local specialist rehabilitation service |
| 350 | Infectious diseases |
| 352 | Tropical medicine |
| 360 | Genito-urinary medicine |
| 361 | Nephrology |
| 370 | Medical oncology |
| 371 | Nuclear Medicine |
| 400 | Neurology |
| 401 | Clinical Neurophysiology |
| 410 | Rheumatology |
| 420 | Paediatrics |
| 421 | Paediatric neurology |
| 422 | Neonatology |
| 424 | Well babies |
| 430 | Geriatric medicine |
| 450 | Dental medicine |
| 460 | Medical ophthalmology |
| 499 | Non-UK Provider |
| 500 | Not a treatment function |
| 501 | Obstetrics |
| 502 | Gynaecology |
| 503 | Gynaecological oncology |
| 510 | Not treatment functions |
| 520 | Not treatment functions |
| 560 | Midwife episode |
| 600 | Not a treatment function |
| 610 | General practice with maternity function [Until 31 March 2004] |
| 620 | General practice other than maternity [Until 31 March 2004] |
| 650 | Physiotherapy |
| 651 | Occupational Therapy |
| 652 | Speech and Language Therapy |
| 653 | Podiatry |
| 654 | Dietetics |
| 655 | Orthoptics |
| 656 | Clinical Psychology |
| 657 | Prosthetics |
| 658 | Orthotics |
| 659 | Drama therapy |
| 660 | Art therapy |
| 661 | Music therapy |
| 662 | Optometry |
| 663 | Podiatric surgery |
| 700 | Learning disability |
| 710 | Adult mental illness |
| 711 | Child and adolescent psychiatry |
| 712 | Forensic psychiatry |
| 713 | Psychotherapy |
| 715 | Old age psychiatry |
| 720 | Eating Disorders |
| 721 | Addiction Services [From 2006-07] |
| 722 | Liaison Psychiatry |
| 723 | Psychiatric Intensive Care |
| 724 | Perinatal Psychiatry |
| 725 | Mental health recovery and rehabilitation service |
| 726 | Mental health dual diagnosis service |
| 727 | Dementia assessment service |
| 800 | Clinical oncology |
| 810 | Radiology |
| 811 | Interventional radiology |
| 812 | Diagnostic Imaging |
| 820 | General pathology [Until 31 March 2004] |
| 821 | Blood transfusion [Until 31 March 2004] |
| 822 | Chemical pathology |
| 823 | Haematology [Until 31 March 2004] |
| 824 | Histopathology [Until 31 March 2004] |
| 830 | Immunopathology [Until 31 March 2004] |
| 831 | Medical microbiology [Until 31 March 2004] |
| 832 | Neuropathology [Until 31 March 2004] |
| 834 | Medical virology |
| 840 | Audiology |
| 900 | Community medicine [Until 31 March 2004] |
| 901 | Occupational medicine [Until 31 March 2004] |
| 920 | Diabetic education service |
| 950 | Nursing episode [Until 31 March 2004] |
| 960 | Not a treatment function |
| 000 | Other maternity event |
| 109 | Bariatric Surgery Service |
| 111 | Orthopaedic Service |
| 113 | Endocrine Surgery Service |
| 115 | Trauma Surgery Service |
| 145 | Oral and Maxillofacial Surgery Service |
| 200 | Aviation and Space Medicine Service |
| 230 | Paediatric Clinical Pharmacology Service |
| 240 | Paediatric Palliative Medicine Service |
| 250 | Paediatric Hepatology Service |
| 270 | Paediatric Emergency Medicine Service |
| 326 | Acute Internal Medicine Service |
| 333 | Rare Disease Service |
| 335 | Inherited Metabolic Medicine Service |
| 347 | Sleep Medicine Service |
| 348 | Post-COVID-19 Syndrome Service |
| 431 | Orthogeriatric Medicine Service |
| 451 | Special Care Dentistry Service |
| 461 | Ophthalmic and Vision Science Service |
| 504 | Community Sexual and Reproductive Health Service |
| 670 | Urological Physiology Service |
| 673 | Vascular Physiology Service |
| 675 | Cardiac Physiology Service |
| 677 | Gastrointestinal Physiology Service |
| 730 | Neuropsychiatry Service |