Modifier 24 denotes an unrelated evaluation and management (E/M) service performed by the same physician or qualified healthcare professional during a postoperative global period. Per CPT guidance, it is used only with E/M codes (not procedure codes) when the visit addresses a problem distinct from the condition that required the surgery; documentation must show a separate diagnosis and that the visit is not routine post‑operative care. The same‑physician or same‑specialty/group rule applies when reporting modifier 24.

Billing and reimbursement vary by payer. Under CPT-based private payer rules, modifier 24 signals the E/M visit is outside the global surgical package and is typically eligible for separate payment when supported by clear documentation that the issue is unrelated to the original procedure. By contrast, Medicare generally considers most complications (for example, infections or seromas) to be included in the global period and will not pay separately for such related postoperative E/M care; if the complication requires return to the operating room, modifier 78—not 24—would apply.

Proper use of modifier 24 helps avoid denials and supports appropriate payment for unrelated E/M services rendered during a global period. Always append the modifier to the E/M code, link the visit to a distinct diagnosis code, and verify specific payer rules before billing, since payer policies (especially Medicare) can differ from CPT guidance.