NCCI edits: how procedure-to-procedure edits work

What are NCCI edits?

The National Correct Coding Initiative (NCCI) is a CMS program that promotes correct coding and controls improper coding that leads to inappropriate payment of Medicare Part B claims. The 2026 NCCI Policy Manual for Medicare Services says the program has three kinds of edit: procedure-to-procedure (PTP) edits, medically unlikely edits and add-on code edits.

All three look at services reported by one provider for one patient on one date of service. This page covers PTP edits and the modifier indicator; unit limits have their own page, medically unlikely edits.

How does a procedure-to-procedure edit work?

Each PTP edit is a pair of codes, a Column One code and a Column Two code. When you report both for the same beneficiary on the same date of service, Medicare pays the Column One code and denies the Column Two code unless a clinically appropriate NCCI PTP-associated modifier is allowed and reported. CMS states this on its Medicare PTP edits page.

CMS publishes one set of files for practitioners and one for hospital outpatient services. The Q4 2026 release is version v323r0, effective October 1, 2026, and each set is split into four files of roughly 475,000 (hospital) or 675,000 (practitioner) records.

Every row carries an effective date and a deletion date. CMS says only edits with a blank or asterisk deletion date are active, and the manual says an edit applies to the period in which it is effective. For an old date of service, look in the file that was current on that date, not today's.

What does the NCCI modifier indicator 0, 1 or 9 mean?

The modifier indicator tells you whether a modifier can get a Column Two code paid. The manual calls it the Correct Coding Modifier Indicator (CCMI), and it sits in the PTP file next to each pair.

For paired organs, most edits carry indicator 1 because the codes can be reported on opposite sides. On contiguous structures in the same organ or region at one encounter, the manual says the modifiers generally should not be used.

Which modifiers bypass an NCCI edit?

The manual lists the NCCI PTP-associated modifiers in three groups. Modifiers 22, 76 and 77 are not on the list, so using one of them never bypasses a PTP edit.

The manual sets a hard condition: a modifier must not be appended to a code solely to bypass an edit when the clinical circumstances do not justify it. If Medicare restricts a modifier, it can bypass an edit only when those restrictions are met. The modifier 76 page explains why.

Who has to follow NCCI edits?

Medicare contractors apply them to Part B practitioner claims and many outpatient facility claims. Other payers decide for themselves.

If a commercial remit cites a bundling edit, ask that payer for the edit source and its version on the date of service.

How do I look up NCCI edits for two CPT codes?

You download the PTP file for the claim type and quarter, then find the row that lists your two codes. CMS says plainly that it does not provide a look-up service or a clean claims tool.

How often do NCCI edits change?

CMS publishes four versions a year, and MACs implement them on January 1, April 1, July 1 and October 1. The Policy Manual is revised once a year; the current edition took effect January 1, 2026.

Edits can also be fixed between quarters with replacement files. In one case, CMS withdrew PTP edits between code 90480 and G0008, G0009 and G0010 retroactive to July 1, 2025, in a replacement file issued October 14, 2025, and MACs were to reprocess affected claims within 30 business days. Otherwise a change is not retroactive, and MACs may reopen impacted claims that providers bring to their attention.

What does an NCCI denial look like on the remit?

Expect a claim adjustment reason code that points to bundling. X12 defines CARC 236 as a procedure or procedure/modifier combination that is not compatible with another one provided on the same day under the National Correct Coding Initiative or workers compensation rules. A remark code that fits is RARC N20, "Service not payable with other service rendered on the same date." The CO-236 page walks through the line. Payers choose which reason code an edit maps to, so read the remark code before you decide it was an NCCI denial.

The liability rule matters for write-offs. The manual says codes denied under PTP edits may not be billed to the Medicare beneficiary, and the provider cannot use an ABN to shift the cost, because these denials rest on incorrect coding rather than medical necessity.

What can I do when an NCCI edit denies a claim?

Appeal to your MAC, not to CMS or the NCCI contractor. The manual says the NCCI contractor cannot process claim appeals or forward them.

1. Pull the PTP file in force on the date of service and confirm the pair, the indicator and the dates.
2. Decide if it is a clerical miss. Under 42 CFR 405.980(a)(3), clerical errors such as inaccurate data entry are processed as reopenings, and a party can ask for a reopening within 1 year for any reason.
3. If the record shows a separate encounter, site or specimen, file a redetermination with the note and operative report. 42 CFR 405.942 sets 120 calendar days from receipt of the notice, with receipt presumed 5 days after the notice date.
4. If you think the edit itself is wrong, email NCCIPTPMUE@cms.hhs.gov with the code pair and your rationale. Leave out protected health information. That route reviews the edit; it does not reverse a claim.

The Medicare appeal levels page covers what comes after a redetermination.

If this rule is costing you claims, our denial management team can help, and our medical coding and billing and coding audits teams check edit handling before claims go out.