What Is Modifier 59 in Medical Billing? The 2026 Definition, Box 24D Placement, and Distinct Procedural Service Rule
Definition: modifier 59 in medical billing is a CPT modifier that flags a distinct procedural service, telling the payer that two procedures normally bundled under National Correct Coding Initiative (NCCI) edits were separate and independent on the same date of service. That’s the definition CMS uses in MLN1783722, Proper Use of Modifiers 59, XE, XP, XS, […]