An add-on code is a HCPCS/CPT code that describes a service that, with one exception (see next paragraph), is always performed in conjunction with another primary service. An add-on code with one exception is eligible for payment only if it is reported with an appropriate primary procedure performed by the same practitioner. An add-on code with one exception is never eligible for payment if it is the only procedure reported by a practitioner.
The Internet Only Manual, Claims Processing Manual, Publication 100-04, Chapter 12, Section 0.6.12(I) requires a provider to report CPT code 99292 (Critical care, evaluation and management of the critically ill or critically injured patient; each additional 30 minutes (List separately in addition to code for primary service)) without its primary code CPT code 99291 (Critical care, evaluation and management of the critically ill or critically injured patient; first 30-74 minutes) if two or more physicians of the same specialty in a group practice provide critical care services to the same patient on the same date of service. For the same date of service only one physician of the same specialty in the group practice may report CPT code 99291 with or without CPT code 99292, and the other physician(s) must report their critical care services with CPT code 99292.
Add-on codes may be identified in three ways per CMS Transmittal 2636
- The code is listed in this CR or subsequent ones as a Type I, Type II, or Type III, add-on code.
- On the Medicare Physician Fee Schedule Database an add-on code generally has a global surgery period of “ZZZ”.
- In the CPT Manual an add-on code is designated by the symbol “+”. The code descriptor of an add-on code generally includes phrases such as “each additional” or “(List separately in addition to primary procedure).”
CMS has divided the add-on codes into three Groups to distinguish the payment policy for each group.
- Type I – This type of add-on code has a limited number of identifiable primary procedure codes. The CR lists the Type I add-on codes with their acceptable primary procedure codes. A Type I add-on code, with one exception, is eligible for payment if one of the listed primary procedure codes is also eligible for payment to the same practitioner for the same patient on the same date of service
- Type II –. A Type II add-on code does not have a specific list of primary procedure codes. The CR lists the Type II add-on codes without any primary procedure codes. Claims processing contractors are encouraged to develop their own lists of primary procedure codes for this type of add-on codes. Like the Type I add-on codes, a Type II add-on code is eligible for payment if an acceptable primary procedure code as determined by the claims processing contractor is also eligible for payment to the same practitioner for the same patient on the same date of service.
- Type III – The third type of add-on code has some, but not all, specific primary procedure codes identified in the CPT® manual. CMS advises claims processing contractors that the primary procedure codes in the CPT® manual are not exclusive, and encourages contractors to develop their own lists of additional primary procedure codes.
To reference the Type I, Type II or Type III lists of CMS add-on CPT® codes, see the bottom pages of the transmittal here: https://www.cms.gov/Regulations-and-Guidance/Guidance/Transmittals/Downloads/R2636CP.pdf