Prolonged services codes function as add-on codes to the highest-level Evaluation and Management (E/M) services in certain categories. To use prolonged care, providers must select the primary code based on time, which is explicitly stated in both the CPT® and HCPCS definitions of prolonged services.

For billing purposes, the full 15 minutes of prolonged services must be completed, as these do not follow the CPT® mid-point time rule. The work performed during prolonged care may include both face-to-face and non-face-to-face time with patients. Health care providers should be aware that prolonged care services can no longer be used with psychotherapy codes, and no replacement code exists for this purpose.

CPT® and CMS use different codes with different time thresholds for prolonged care. While CPT® allows only services performed on the calendar day of the visit, for certain codes, CMS allows time on other dates of service. The rules vary and are confusing.

Although CPT® still includes non-face-to-face prolonged care codes 99358 and +99359 for days without face-to-face visits, CMS has designated these as invalid and does not reimburse for them, leaving no replacement options for Medicare patients.

This guide provides detailed information about coding for prolonged services.

Related resources

• Code Prolonged Services with Confidence | Webinar