NCCI Edits (PTP)

National Correct Coding Initiative Procedure-to-Procedure edits prevent billing two CPT codes together that should be bundled. CMS publishes 2.6M practitioner PTP edits and 1.86M outpatient hospital PTP edits, updated quarterly. Each edit has a Modifier Indicator: 0 = never bypass, 1 = bypass with appropriate modifier, 9 = edit deleted. Submitting bundled codes without an allowed modifier triggers a CO-97 denial.