Medicare NCCI FAQ Library
About NCCI
1. What is the National Correct Coding Initiative (NCCI)?
NCCI is a CMS program that consists of coding policies and edits. Providers report procedures or services performed on beneficiaries utilizing Healthcare Common Procedure Coding System (HCPCS)/Current Procedural Terminology (CPT) codes. These codes are submitted on claim forms to fiscal agents for payment. NCCI policies and edits address procedures or services performed by the same provider for the same beneficiary on the same date of service. The coding policies of NCCI are based on coding conventions defined in the American Medical Association’s Current Procedural Terminology Manual, national and local policies and edits, coding guidelines developed by national societies, standard medical and surgical practice, and/or current coding practice.
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Billing and Coding Advice
1. How do I obtain billing and coding advice from the National Correct Coding Initiative (NCCI) Program?
The NCCI program contractor provides general information to the public regarding the NCCI program and edits. However, we do not provide specific billing or coding advice to providers/suppliers. Questions regarding specific claims should be addressed to your claims processing contractor (e.g., your Part A or Part B Medicare Administrative Contractor (MAC) or State Medicaid Agency (SMA)). Providers/suppliers may also find it helpful to contact their national healthcare organization (NHO) or the NHO whose members commonly perform the procedure.
2. What can I do about other commercial payers who deny payment citing NCCI edits?
Some private insurers, including those in the commercial and government benefit markets (e.g., Medicaid managed care organizations and Medicare Advantage Organizations), voluntarily adopt Medicare’s NCCI methodologies. NCCI edits are developed by CMS for the Medicare and Medicaid fee-for-service programs and CMS does not have control over how those edits are implemented by private insurers. Questions regarding specific claims should be addressed to the insurer making the claim denial.
3. Do NCCI edits use diagnosis codes (e.g., ICD-10)?
No, NCCI edits are not based on diagnosis codes.
- 4. Where can I find Medicare NCCI educational resources?
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Medicare National Correct Coding Initiative (NCCI) Policy Manual
1. Where do I find the Medicare National Correct Coding Initiative (NCCI) Policy Manual?
You may view or download the Medicare NCCI Policy Manual here.
2. Where can I find information about the correct coding in the Medicare manuals?
You can find information about the NCCI program in the Medicare Claims Processing Manual, Publication 100-04, Chapter 23 (PDF), Section 20.9. You can find information about correct coding policy in the Medicare Claims Processing Manual, Publication 100-04, Chapter 12 (PDF), Section 30.
NCCI Procedure-to-Procedure (PTP) edits and Medically Unlikely Edits (MUEs) for Current Procedural Terminology (CPT)/Healthcare Common Procedure Coding System (HCPCS) codes apply to services reported by the same provider/supplier for the same beneficiary on the same date of service.
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Medically Unlikely Edits (MUE)
1. What is the Centers for Medicare & Medicaid Services (CMS) MUE program?
The CMS MUE program was developed to reduce the paid claims error rate for Medicare claims. MUEs are designed to reduce errors due to clerical entries and incorrect coding based on criteria such as anatomic considerations, HCPCS/CPT code descriptors, CPT coding instructions, established CMS policies, nature of a service/procedure, nature of an analyte, nature of the equipment, prescribing information, and claims data.
2. What is a Medically Unlikely Edit (MUE)?
An MUE is a unit of service edit for a Healthcare Common Procedure Coding System (HCPCS)/Current Procedural Terminology (CPT) code for services rendered by a single provider/supplier to a single beneficiary on the same date of service. An MUE is the maximum unit(s) of service that would be reported for an HCPCS/CPT code on the vast majority of appropriately reported claims. MUEs are adjudicated either as claim line edits or date of service edits. Not all HCPCS/CPT codes have an MUE. (See question five for guidance on reporting medically reasonable and necessary services in excess of an MUE value for claim line edits.)
3. Are there NCCI Medicare date of service MUEs and Claim Line MUEs for HCPCS/CPT codes?
There are both date of service and claim line MUEs. CMS publishes which codes have a date of service and which codes have claim line MUEs. For date of service MUEs, the claims processing system sums all units of service (UOS) on all claim lines with the same HCPCS/CPT code and date of service. The MUE files on the CMS NCCI web page display an MUE Adjudication Indicator (MAI) for each HCPCS/CPT code. An MAI of “1” indicates that the edit is a claim line MUE. An MAI of “2” or “3” indicates that the edit is a date of service MUE. Further information is available in MM8853 (PDF).
4. How are claims adjudicated with MUEs?
MUEs are either claim line edits or date of service edits. If the MUE is a claim line edit, each line of a claim is adjudicated against the MUE value for the HCPCS/CPT code on that claim line. If the UOS on the claim line exceeds the MUE value, all UOS for that claim line are denied. If the same code is reported on more than one line of a claim by using CPT modifiers, each line of the claim is adjudicated separately against the MUE value of the code on that claim line.
If the MUE is a date of service MUE, all UOS for the HCPCS/CPT code reported by the same provider/supplier for the same beneficiary for the same date of service are summed. The summed value is compared to the MUE value. If the sum is greater than the MUE value, all UOS for the code on the current claim are denied.
5. How do I report medically reasonable and necessary Units of Service (UOS) in excess of an MUE value?
For MUEs that are adjudicated as claim line edits, each line of a claim is adjudicated separately against the MUE value for the code on that line. The appropriate use of HCPCS/CPT modifiers to report the same code on separate lines of a claim will enable a provider/supplier to report medically reasonable and necessary UOS in excess of a claim line edit. Further information is available in MM8853 (PDF).
6. What’s are the 3 provider-type choices of MUEs?
There are separate MUE files, depending on the provider/supplier. The How to Use The National Correct Coding Initiative (NCCI) Tools (PDF) booklet shows you how to search for edits, how to interpret the edits, and how to use the resources on the NCCI webpages.
7. How often are the NCCI PTP edits and MUEs updated?
The NCCI PTP edit files and MUE files are updated at least quarterly.
8. How do I know if a PTP edit is in effect?
You can learn how to find and interpret the PTP edit tables in the booklet How to Use the National Correct Coding Initiative (NCCI) Tools (PDF). It’s important to check whether there is a Deletion Date entered.
9. Has CMS published the MUE values for HCPCS/CPT codes?
Most MUE values are visible to providers on the webpage, but CMS considers some MUEs confidential, and they aren't released. The public or confidential status of MUEs may change.
10. Can an Advanced Beneficiary Notice (ABN) be used to bill the beneficiary for services denied due to an MUE?
It’s inappropriate to issue an ABN based on an MUE. A denial of services due to an MUE is a coding denial, not a medical necessity denial. The presence of an ABN doesn’t shift liability to the beneficiary for UOS denied based on an MUE. If, during reopening or redetermination, medical records are provided with respect to an MUE denial for an edit with an MUE Adjudication Indicator (MAI) of “3,” MACs will review the records to determine if the provider/supplier actually furnished units in excess of the MUE, if the codes were used correctly, and whether the services were medically reasonable and necessary. If the units were actually provided but one of the other conditions is not met, a change in denial reason may be warranted (for example, a change from the MUE denial based on incorrect coding to a determination that the item/service is not reasonable and necessary under section 1862(a)(1)). This may also be true for certain edits with an MAI of “1.” CMS interprets the notice delivery requirements under Section 1879 of the Social Security Act (the Act) as applying to situations in which a provider/supplier expects the initial claim determination to be a reasonable and necessary denial. Consistent with NCCI guidance, denials resulting from MUEs are not based on any of the statutory provisions that give liability protection to beneficiaries under Section 1879 of the Act. Further information is available in Medicare Learning Network® (MLN) Matters MM8853 (PDF).
11. If two different physicians in my clinic perform the same procedure or service on the same day for the same beneficiary, will both services be paid?
NCCI PTPs and MUEs for HCPCS/CPT codes apply to services reported by the same provider/supplier for the same beneficiary on the same date of service. The NCCI program contractor provides general information to the public regarding the NCCI program and edits. However, we do not provide specific billing or coding advice to providers / suppliers, and we do not deal with payment issues. Questions regarding specific claims should be addressed to your claims processing contractor (e.g., your Part A or B Medicare Administrative Contractor (MAC) or State Medicaid Agency).
12. How are MUEs developed?
MUEs are developed based on HCPCS/CPT code descriptors, CPT coding instructions, anatomic considerations, established CMS policies, nature of service or procedure, nature of analyte, nature of equipment, prescribing information, and clinical judgment. MUE values are not utilization guidelines and do not represent UOS that may be reported without concern about medical review. Providers should continue to only report services that are medically reasonable and necessary. Providers may be subject to medical review of their claims even if they report UOS less than or equal to the MUE value for a code.
13. How do I request a change in the MUE value for a HCPCS/CPT code?
It is generally recommended that the party contact the National Healthcare Organization (NHO) whose members perform the procedure. The NHO may be able to clarify the reporting of the code in question. If the NHO agrees that the MUE value should be modified, its support and assistance may be helpful in requesting the modification of an MUE value. If a provider or supplier, healthcare organization, or other interested party believes that a MUE value should be modified, they should email the CMS NCCI mailbox at NCCIPTPMUE@cms.hhs.gov. The party should include exact codes, an alternative MUE value, the rationale for the alternative MUE value, and any supporting documentation. **NOTE** Any submissions made to the NCCI contractor that contain Personally Identifiable Information (PII) or Protected Health Information (PHI) are automatically discarded, regardless of the content, in accordance with federal privacy rules with which the NCCI Contractor must comply.
14. Where can I find information about the MUEs other than about MUE values for specific HCPCS/CPT codes?
All available MUE tables for Medicare for the most recent quarter are published on the CMS webpage. You can find information about MUEs in the Medicare NCCI Policy Manual, Chapter 1, Section V.
15. What determines the UOS for an MUE?
UOS are defined by the code descriptor (also referred to as the narrative description of the code). Examples below show the HCPCS code, followed by the code descriptor, followed by the UOS:
- J1100 “Injection, dexamethasone sodium phosphate, 1 mg” the unit of service is 1 mg
- J0670 “Injection, mepivacaine hydrochloride, per 10 ml” the unit of service is 10 ml
- J7180 Injection, factor xiii (antihemophilic factor, human), 1 IU, the unit of service is 1 International Unit (IU)
- 99292 “Critical care, evaluation and management of the critically ill or critically injured patient; each additional 30 minutes” the unit of service is 30 minutes
16. How do you correctly report bilateral procedures?
You can find information on bilateral procedures in SE1422, Medically Unlikely Edits (MUE) and Bilateral Surgical Procedures, and in the Medicare NCCI Policy Manual, Chapter 1, Section V.
17. What does an MUE Adjudication Indicator (MAI) mean?
The MUE files on the CMS NCCI webpage display an MAI for each HCPCS/CPT code. An MAI of “1” indicates that the edit is a claim line edit. An MAI of “2” or “3” indicates that the edit is a date of service MUE.
The MLN article MM8853 (PDF) may also answer some of your questions regarding MUEs/MAIs.
18. Is there a deadline for submitting a request for edit review and change?
NCCI edit files are updated at least quarterly. Each request is individually considered, and the amount of time to complete a determination varies depending individual factors. There are no deadlines for submitting a request to the CMS NCCI program. Once a decision is reached, CMS sends a reply.
19. Where do I find previous versions of MUE edit files?
CMS posts only the current quarter and previous quarter’s files for public use on the Medicare NCCI Edits webpage.
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Procedure-to-Procedure (PTP) Edits
1. What does "Column One" or “Column Two” mean in the Column One/Column Two NCCI edits table?
Detailed instruction regarding the use of “Column One” or “Column Two” may be found in How to Use The Medicare National Correct Coding Initiative (NCCI) Tools (PDF).
2. How long are the Procedure-to-Procedure (PTP) edits and Medically Unlikely Edits (MUEs) in the NCCI program valid?
There is no set time period for which NCCI edits are valid. Some edits may remain in place indefinitely. The PTP edits and MUEs may be updated at least quarterly.
3. Where is the effective date of a PTP edit?
The effective date of an edit will be listed in the PTP edit file.
4. If each of the Healthcare Common Procedure Coding System (HCPCS)/Current Procedural Terminology (CPT) coded procedures listed in the NCCI PTP edit is performed by two different physicians in my clinic on the same day for the same beneficiary, will both services be paid?
NCCI PTP edits for HCPCS/CPT codes apply to services reported by the same provider/supplier for the same beneficiary on the same date of service.
The NCCI program contractor provides general information to the public regarding the NCCI program and edits. However, we do not provide specific billing or coding advice to providers or suppliers, and we do not deal with payment issues. Questions regarding specific claims should be addressed to your claims processing contractor (e.g., your Part A or Part B Medicare Administrative Contractor (MAC) or State Medicaid Agencies (SMA)).
5. How do NCCI edits apply to Critical Access Hospitals (CAHs)?
PTP and Add-on Code (AOC) edits are applied to Type of Bill “85X, and OPPS flag = 2” as explained in the narrative in the Outpatient Code Editor (OCE) Quarterly Release Files and in MLN article SE18012 (PDF). All claims submitted on TOB 85X Critical Access Hospitals (CAHs) are tested against MUEs.
The booklet How to Use the Medicare National Correct Coding Initiative (NCCI) Tools (PDF) provides more information.
6. What does edit rationale mean?
General information about edit rationale can be found in the Medicare NCCI Policy Manual, Chapter 1, and general categories of edit rationale can be found in the Medicare NCCI Correspondence Language Manual.
7. How do I ask CMS to reconsider a PTP edit?
If you would like to make a Medicare PTP reconsideration request, please email us at NCCIPTPMUE@cms.hhs.gov with exact code pairs, detailed reconsideration, new proposed edits, and any supporting documentation you have. **NOTE** Any submissions made to the NCCI contractor that contain Personally identifiable information (PII) or Protected Health Information (PHI) are automatically discarded, regardless of the content, in accordance with federal privacy rules the NCCI Contractor must comply with.
8. Although a PTP edit has been deleted, there is a Correct Coding Modifier Indicator (CCMI) present in the field; what does this mean?
A deleted edit is one where no edit exists for that code pair and there is a deletion date in Column E of the PTP tables. Therefore, when reporting these services, no modifier is required. In the current PTP edit tables, Column E shows the deletion date of the deleted code pairs and Column F shows the modifier status when the edit was active.
9. What does the CCMI mean?
Each NCCI PTP edit is assigned Correct Coding Modifier Indicator (CCMI). A CCMI of "0" indicates that NCCI PTP-associated modifiers cannot be used to bypass the edit. A CCMI of "1" indicates that NCCI PTP associated modifiers may be used to bypass an edit under appropriate circumstances. A CCMI of "9" indicates that the use of NCCI PTP-associated modifiers is not specified. This indicator is used for all code pairs that have a deletion date that is the same as the effective date. This indicator prevents blank spaces from appearing in the indicator field. The booklet How to Use the Medicare National Correct Coding Initiative (NCCI) Tools (PDF) provides more information regarding PTP edits and CCMIs.
10. What does it mean if there is a termination date for a PTP edit (Column E) and there is a Correct Coding Modifier Indicator (CCMI) in the Modifier Column (Column F)?
If there is a deletion date in the Deletion Date Column, Centers for Medicare & Medicaid Services (CMS) deleted the edit. The edit and CCMI are active between the effective date and termination date. An edit is not active if the effective and deletion date are the same and the CCMI is “9”.
11. What does it mean if there is an effective date (Column D) but no deletion date (Column E) for an edit?
An active edit has an effective date but no deletion date.
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NCCI Modifiers
1. What modifiers are allowed with the National Correct Coding Initiative (NCCI) Procedure-to-Procedure (PTP) edits?
Modifiers that may be used under appropriate clinical circumstances to bypass an NCCI PTP edit include:
- Anatomic modifiers: E1-E4, FA, F1-F9, TA, T1-T9, LT, RT, LC, LD, RC, LM, RI
- Global surgery modifiers: 24, 25, 57, 58, 78, 79
- Other modifiers: 27, 59, 91, XE, XS, XP, XU
It’s very important that NCCI PTP-associated modifiers only be used when appropriate. In general, these circumstances relate to separate patient encounters, separate anatomic sites, or separate specimens. (See subsequent discussion of modifiers in this section.) Most edits involving paired organs or structures (e.g., eyes, ears, extremities, lungs, kidneys) have NCCI PTP modifier indicators of “1” because the two codes of the code pair edit may be reported if performed on the contralateral organs or structures. Most of these code pairs should not be reported with NCCI PTP-associated modifiers when performed on the ipsilateral organ or structure unless there is a specific coding rationale to bypass the edit.
The presence of an NCCI PTP edit indicates that the two codes generally can’t be reported together unless the two corresponding procedures are performed at two separate patient encounters or two separate anatomic locations. Similarly, if the two corresponding procedures are performed at the same patient encounter and in contiguous structures in the same organ or anatomic region, NCCI PTP-associated modifiers generally shouldn’t be used.
Modifier 59, XE, XP, XS, & XU (MLN 1783722 (PDF)) may be used only if no other appropriate modifier describes the service. The article provides more information on the appropriate use of the Modifiers 59, XE, XP, XS, & XU.
2. How do I know which modifier to use to bypass an edit?
General information about NCCI-associated modifiers can be found in the Medicare NCCI Policy Manual, Chapter 1, Section E.
3. Can these modifiers that are associated with the NCCI PTP edits be used with all the Column One/Column Two correct coding edits?
No, there are some Column One/Column Two correct coding edits which CMS does not think would ever warrant the use of any modifier associated with the NCCI PTP edits. These code pairs are assigned a Correct Coding Modifier Indicator (CCMI) of “0.”
4. If I have a situation where I think a modifier associated with the NCCI program should be used, is there someone who can tell me if I am using the modifier properly?
Information on the proper use of modifiers is available in the CMS Claims Processing Manual (PDF), Publication 100-04, Chapter 12 and the Medicare NCCI Policy Manual, Chapter 1, Section E. Specific billing and reporting questions should be directed to your local MAC in writing.
5. How should modifier 25 be reported under the NCCI?
Modifier 25 may be appended to an Evaluation & Management (E&M) code when reported with another procedure or other service, on the same day of service to indicate a “significant and separately identifiable” E&M service when appropriate. For additional information, please see the Medicare NCCI Policy Manual, Chapter 1, Section E.
Please refer to the Medicare Claims Processing Manual (PDF), Publication 100-04, Chapter 12, Section 30.6.6, regarding the use of Current Procedural Terminology (CPT) modifier 25.
6. How should modifiers 59 or XE, XP, XS, XU be reported under the NCCI program?
For your convenience, find more information regarding Modifiers 59 or XE, XP, XS, XU in CMS MLN 1783722 (PDF). The article provides more information on the appropriate use of the 59 or XE, XP, XS, XU modifier.
7. How should modifier 91 be reported under the NCCI program?
The CPT Professional defines organ and disease specific panels of laboratory tests. If a laboratory performs all tests included in one of these panels, the laboratory shall report the CPT code for the panel. If the laboratory repeats 1 of these component tests as a medically reasonable and necessary service on the same date of service, the CPT code corresponding to the repeat laboratory test may be reported with modifier 91 appended (see the Medicare NCCI Policy Manual, Chapter X, Section C, Organ or Disease Oriented Panels).
If a HCPCS/CPT code has an MUE that is adjudicated as a claim line edit, (i.e., MAI equal to “1”) appropriate use of CPT modifiers (i.e., 59 or XE, XP, XS, XU; 76, 77, 91, anatomic) may be used to report the same HCPCS/CPT code on separate lines of a claim. Each line of the claim with that HCPCS/CPT code will be separately adjudicated against the MUE value for that HCPCS/CPT code. Claims processing contractors have rules limiting use of these modifiers with some HCPCS/CPT codes.
Based on the Internet-only Manuals (IOM) Medicare Claims Processing Manual, Publication 100-04, Chapter 16, Section 100.5.1, the repeat testing can’t be performed to “confirm initial results; due to testing problems with specimens and equipment or for any other reason when a normal, one-time, reportable result is all that is required.”
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Published PTP and MUE Files
1. How do I know what changed in the National Correct Coding Initiative (NCCI) Procedure-to-Procedure (PTP) edits and Medically Unlikely Edits (MUE) files from quarter to quarter?
CMS posts the current and previous quarter’s PTP edit and MUE files and change report files. The change report files are available to the public, and may be found on the PTP and MUE webpages.
2. Why does it sometimes appear that CMS adds edits to the NCCI program in one version, and then in the next version changes or deletes those edits?
CMS developed the NCCI program to promote national correct coding methodologies and to control improper coding that leads to inappropriate payment of Part B claims. The coding policies are based on coding conventions defined in the American Medical Association’s (AMA) Current Procedural Terminology (CPT) Manual, national and local Medicare policies and edits, coding guidelines developed by national societies, standard medical and surgical practice, or current coding practice. The NCCI program is responsible for developing, revising, and maintaining NCCI edits, responding to inquiries regarding the NCCI program, and promoting program integrity and compliance. Changes in the NCCI program are the result of comments submitted to CMS. Prior to implementing new edits, CMS generally provides a review and comment period to representative national organizations that may be impacted by the edits. However, there are situations when CMS thinks that it is prudent to implement edits prior to completion of the review and comment period. The CMS Central Office evaluates the input from all sources and decides which edits are modified, deleted, or added each quarter.
3. There are some software coding programs that already contain the NCCI PTP edits and published MUEs. Do I still need to obtain the edits from the CMS website?
At this time, the official method for Medicare providers or suppliers to receive the NCCI PTP edits and published MUEs is through the CMS Medicare NCCI webpage. It is the responsibility of the entity billing Medicare to ensure that they bill correctly. Other government and private insurers may choose to adopt Medicare’s NCCI methodologies.
The application of Medicare’s NCCI methodologies, and thereby the application of Medicare payment policies and rules to claims other than Medicare Part B claims, may result in denials by other plans. Plans that voluntarily choose to adopt Medicare’s NCCI methodologies should review their edits and consider deactivating individual edits that conflict with their own benefit and coverage determinations. If you have questions or concerns regarding this process, please contact your payer directly.
4. How often are the NCCI PTP edits and MUEs updated?
The NCCI PTP edits and MUEs are usually updated at least quarterly.
5. If I receive a bundling message that says something is included in a service billed on the same day, and I don’t find evidence of this edit in the latest version update of the NCCI program, who should I ask about this denial?
Contact your local Medicare Part A/B Medicare Administrative Contractor (MAC) (PDF) about other edits that may be in place on a national or local level that are not NCCI edits.
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