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National Correct Coding Initiative Edits

Important notice to all NCCI Users concerning the National Correct Coding Initiative Policy Manual for Medicare Services:

The annual updated version of the National Correct Coding Initiative Policy Manual for Medicare Services is effective January 1, 2018.  Additions/revisions to the manual have been italicized in red font.

Additional prior versions of the National Correct Coding Initiative Policy Manual for Medicare Services are now available.

National Correct Coding Initiative

The CMS developed the National Correct Coding Initiative (NCCI) to promote national correct coding methodologies and to control improper coding leading to inappropriate payment in Part B claims. The CMS developed its coding policies based on coding conventions defined in the American Medical Association's CPT Manual, national and local policies and edits, coding guidelines developed by national societies, analysis of standard medical and surgical practices, and a review of current coding practices. The CMS annually updates the National Correct Coding Initiative Coding Policy Manual for Medicare Services (Coding Policy Manual). The Coding Policy Manual should be utilized by carriers and FIs as a general reference tool that explains the rationale for NCCI edits.

Carriers implemented NCCI Procedure-to-Procedure(PTP) edits within their claim processing systems for dates of service on or after January 1, 1996 and began implementing  Medically Unlikely (MUE) edits on January 1, 2007.

A corresponding set of PTP  edits is incorporated into the outpatient code editor (OCE) for OPPS and therapy providers (Part B Skilled nursing facilities (SNFs), comprehensive outpatient rehabilitation facilities (CORFs), outpatient physical therapy and speech-language pathology providers (OPTs), and certain claims for home health agencies (HHAs) billing under TOBs 22X, 23X, 75X, 74X, 34X).  Corresponding MUE edits are similarly implemented within the Fiscal Intermediary Shared System (FISS).

The purpose of the NCCI Procedure-to-Procedure (PTP) edits is to prevent improper payment when incorrect code combinations are reported. The NCCI contains one table of edits for physicians/practitioners and one table of edits for outpatient hospital services. The Column One/Column Two Correct Coding Edits table and the Mutually Exclusive Edits table have been combined into one table and include PTP code pairs that should not be reported together for a number of reasons explained in the Coding Policy Manual.  The purpose of the NCCI MUE program is to prevent improper payments when services are reported with incorrect units of service.

The Correspondence Language Manual available below has been written and maintained for utilization by the Medicare Contractors to answer routine correspondence inquiries about the NCCI procedure to procedure (PTP) and MUE edits. The general correspondence language paragraphs explain the rationale for the edits. The section-specific examples add further explanation to the PTP or MUE edits and are sorted by edit rationale and CPT code section (00000, 10000, 20000, etc.). Please refer to the Introduction of this Manual for additional guidance about its use.

Inquiries about the NCCI program, other than those related to  NCCI (PTP, MUE and Add-On) edits, should be sent to the following email address:

This web page provides information to providers on Medicare's NCCI edits but does not address specific NCCI edits. If the viewer has concerns about specific NCCI edits, he/she may submit comments in writing to:

National Correct Coding Initiative
Correct Coding Solutions LLC
P.O. Box 907
Carmel, IN 46082-0907

Attention: Niles R. Rosen, M.D., Medical Director and Linda S. Dietz, RHIA, CCS, CCS-P, Coding Specialist

Fax #: 317-571-1745