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 | |
|---|---|---|---|
| UF | Services provided in the morning | Apr 01, 2003 | |
| UG | Services provided in the afternoon | Apr 01, 2003 | |
| UH | Services provided in the evening | Apr 01, 2003 | |
| UJ | Services provided at night | Jan 01, 2017 | |
| UK | Services provided on behalf of the client to someone other than the client (collateral relationship) | Apr 01, 2003 | |
| UN | Two patients served | Jan 01, 2004 | |
| UP | Three patients served | Jan 01, 2004 | |
| UQ | Four patients served | Jan 01, 2004 | |
| UR | Five patients served | Jan 01, 2004 | |
| US | Six or more patients served | Jan 01, 2004 | |
| V1 | Demonstration modifier 1 | Jan 01, 2017 | |
| V2 | Demonstration modifier 2 | Jan 01, 2017 | |
| V3 | Demonstration modifier 3 | Jan 01, 2017 | |
| V4 | Demonstration modifier 4 | Oct 01, 2020 | |
| V5 | Vascular catheter (alone or with any other vascular access) | Jul 01, 2010 | |
| V6 | Arteriovenous graft (or other vascular access not including a vascular catheter) | Jul 01, 2010 | |
| V7 | Arteriovenous fistula only (in use with two needles) | Jul 01, 2010 | |
| V8 | Infection present | Apr 01, 2012 | |
| V9 | No infection present | Apr 01, 2012 | |
| VM | Medicare diabetes prevention program (mdpp) virtual make-up session | Apr 01, 2018 | |
| VP | Aphakic patient | Jan 01, 1997 | |
| X1 | Continuous/broad services: for reporting services by clinicians, who provide the principal care for a patient, with no planned endpoint of the relationship; services in this category represent comprehensive care, dealing with the entire scope of patient problems, either directly or in a care coordination role; reporting clinician service examples include, but are not limited to: primary care, and clinicians providing comprehensive care to patients in addition to specialty care | Jan 01, 2018 | |
| X2 | Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services | Jan 01, 2018 | |
| X3 | Episodic/broad services: for reporting services by clinicians who have broad responsibility for the comprehensive needs of the patient that is limited to a defined period and circumstance such as a hospitalization; reporting clinician service examples include but are not limited to the hospitalist's services rendered providing comprehensive and general care to a patient while admitted to the hospital | Jan 01, 2018 | |
| X4 | Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period | Jan 01, 2018 |