| 26 | Modifier 26 (Professional Component) identifies and bills only the professional portion of a split service — the physician’s interpretation, report, and medical judgment — when the technical… | - Use CPT Modifier -26 when you are billing only the professional component (PC) of a split‑bill eligible service—i.e., you performed the physician interpretation, medical judgment and prepared a… |
| 59 | Modifier 59 indicates a distinct procedural service when two procedures that are not normally billed together are clinically and procedurally separate. The CPT definition (as reiterated by CMS)… | - Use modifier -59 to report a distinct procedural service when documentation supports that the procedure reported is not normally billed together with another service on the same day because of a… |
| 90 | Modifier ‑90 (Reference/Outside Laboratory) indicates that a laboratory test was performed by an entity other than the treating or reporting provider. The American Medical Association defines… | - Use CPT modifier -90 when a laboratory test is performed by an outside/reference laboratory (an entity other than the treating or reporting physician or qualified professional) and the claim needs… |
| 91 | Modifier 91 — “Repeat Clinical Diagnostic Laboratory Test” — is appended when the exact same CPT laboratory test is performed more than once for the same patient on the same day because serial,… | - Use modifier 91 when the exact same CPT laboratory test is performed more than once on the same patient on the same date because serial or repeated testing is medically necessary to monitor… |
| P1 | Modifier P1 indicates an ASA Physical Status I — a normal healthy patient — and is appended to anesthesia CPT codes (00100–01999) based on the anesthesiologist’s clinical assessment. It documents the… | - When to apply: Use modifier P1 on anesthesia CPT codes (00100–01999) when the anesthesia provider assigns ASA Physical Status I — a normal healthy patient (non‑smoker, minimal or no alcohol use).… |