CPT® modifier -57 (“Decision for Surgery”) is appended to an Evaluation and Management (E/M) service when that encounter results in the initial decision to perform a major surgery (a procedure with a 90‑day global period) on the day of or the day before the operation. CMS and AMA guidance—and payer guidance echoed by coding authorities like AAPC—state that such E/M services are not included in the global surgical package when modifier 57 is appropriately reported, so the E/M may be billed separately. Documentation must clearly show the decision for surgery was made during that specific encounter; visits used only for preoperative clearance or where the decision was made earlier do not qualify. Practically, modifier 57 is used only when the same provider (or same tax ID) who billed the E/M also performs the major surgery, and it is not appropriate for minor procedures (0‑ or 10‑day global periods), where modifier 25 may apply if a separately identifiable E/M exists.

When modifier 57 is omitted for an eligible visit, payers commonly consider the E/M included in the surgical global period and deny separate reimbursement, so correct use can recover significant E/M revenue (examples from AAPC show typical values for ER or inpatient E/Ms). Carriers monitor modifier 57 usage and unusually high application can prompt reviews, education, or prepayment screening. Always ensure clinical notes explicitly state that the surgical decision was made on the day of or the day before the major procedure to support separate billing.