A modifier provides the means by which the reporting physician or provider can indicate that a service or procedure that has been performed has been altered by some specific circumstance but not changed in its definition or code.
Level I modifiers are codes and descriptors copyrighted by the American Medical Association's current procedural terminology (CPT).
Level II modifiers are codes and descriptors approved and maintained jointly by the alpha-numeric editorial panel (consisting of CMS, the Health Insurance Association of America, and the Blue Cross and Blue Shield Association).
| Modifier | Description | Effective | |
|---|---|---|---|
| ST | Related to trauma or injury | Jan 01, 2003 | |
| SU | Procedure performed in physician's office (to denote use of facility and equipment) | Jan 01, 2003 | |
| SV | Pharmaceuticals delivered to patient's home but not utilized | Jan 01, 2003 | |
| SW | Services provided by a certified diabetic educator | Apr 01, 2004 | |
| SY | Persons who are in close contact with member of high-risk population (use only with codes for immunization) | Jan 01, 2005 | |
| SZ | Habilitative services | Jan 01, 2018 | |
| T1 | Left foot, second digit | Jan 01, 1999 | |
| T2 | Left foot, third digit | Jan 01, 1999 | |
| T3 | Left foot, fourth digit | Jan 01, 1999 | |
| T4 | Left foot, fifth digit | Jan 01, 1999 | |
| T5 | Right foot, great toe | Jan 01, 1999 | |
| T6 | Right foot, second digit | Jan 01, 1999 | |
| T7 | Right foot, third digit | Jan 01, 1999 | |
| T8 | Right foot, fourth digit | Jan 01, 1999 | |
| T9 | Right foot, fifth digit | Jan 01, 1999 | |
| TA | Left foot, great toe | Jan 01, 1999 | |
| TB | Drug or biological acquired with 340b drug pricing program discount, reported for informational purposes | Jan 01, 2025 | |
| TC | Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles | Jan 01, 1997 | |
| TD | Rn | Jul 01, 2001 | |
| TE | Lpn/lvn | Jul 01, 2001 | |
| TF | Intermediate level of care | Jul 01, 2001 | |
| TG | Complex/high tech level of care | Jul 01, 2001 | |
| TH | Obstetrical treatment/services, prenatal or postpartum | Jul 01, 2001 | |
| TJ | Program group, child and/or adolescent | Jul 01, 2001 | |
| TK | Extra patient or passenger, non-ambulance | Apr 01, 2002 |