What is CPT code 99204?

CPT code 99204 is used to bill for an office or other outpatient visit for an established patient, typically requiring a moderate level of medical decision-making. This code is applicable for visits that involve a detailed history, examination, and medical decision-making of low complexity. It usually pertains to patients who present with new or worsening conditions but do not require emergency evaluation. Overall, it reflects a visit that lasts about 30-39 minutes.