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Distinct Procedural Service Modifiers (59, XE, XP, XS, XU)

Reimbursement Policy:
Distinct Procedural Service Modifiers (59, XE, XP, XS, XU)

Effective Date:
January 1, 2009

Last Revised Date:
April 27, 2023

To provide guidelines for the recognition of distinct procedure modifiers when appropriately appended to procedure codes, other than Evaluation and Management (E & M) services, not normally reported together and identify scenarios where Distinct Procedural Services modifiers will not result in separate payment for services. This policy documents Horizon BCBSNJ's position on reimbursement and reporting services with modifier 59, XE, XP, XS, or XU (collectively referred to as X{EPSU} modifiers) for CMS-1500 submitters.

All products are included, except

  • Products where Horizon BCBSNJ is secondary to Medicare (e.g. Medigap).
  • COB
  • ITS Home In-Network

All Insured and Administrative Services Only (ASO) accounts are included.


Modifier 59: CPT describes modifier 59 as identifying a distinct procedural service. Appendix A of the CPT codebook states, "Under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-E & M services performed on the same day. Modifier 59 is used to identify procedures/services, other than E & M services, that are not normally reported together, but are appropriate under the circumstances.1"

Modifiers X{EPSU}: The X{EPSU} modifiers are described by HCPCS as modifiers to be used for a distinct separate encounter (XE), separate practitioner (XP), separate structure (XS), or unusual non-overlapping service (XU) and are considered subsets of modifier 59 for selective identification.

Horizon BCBSNJ accepts the submission of distinct procedure modifiers for claims processing, but use of such modifiers does not always determine reimbursement eligibility. Modifiers 59 and X{EPSU} are important to the adjudication of the claim because they may result in the override of procedure unbundling edits in Horizon BCBSNJ's claims editing systems as described in more detail below.

  1. Procedure Unbundling: is defined as using two or more procedure codes to describe a service when a single, more comprehensive procedure code exists that more accurately describes the complete service performed. Procedure unbundling edits within the Horizon claims systems include three components: Incidental, Mutually Exclusive, and Rebundling. (See also our ClaimsXten Editing Rules Policy for additional information) These edits generally function as follows:
    • When modifier 59 or X{EPSU} are appended to a reported procedure code, our claims editing systems will override most incidental, mutually exclusive, and rebundling denials, and allow separate reimbursement for that procedure.
    • The incidental, mutually exclusive, and rebundling edits are not overridden when a different diagnosis is submitted, with a line item procedure code, without a modifier that identifies a distinct procedural service.
    • However, a different diagnosis alone does not justify the use of modifier 59 or X{EPSU}.
    • Unlisted procedures are not affected by modifier 59 or X{EPSU}.
  1. Reporting and Documentation Rules and Criteria for Modifier 59: The reporting of modifier 59 or X{EPSU} by a provider must follow Horizon BCBSNJ's requirements for correct coding, as follows:
    • Horizon BCBSNJ requires that modifier 59 or X{EPSU} must be appended to the denied code as described in the National Correct Coding Initiative (NCCI) Column 1/Column 2 edits
    • We follow CPT coding guidelines requiring that modifier 59 only be used when there is no other appropriate established modifier, and "only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. 2"
    • Modifier 59 should only be used if no more descriptive modifier is available, such as X{EPSU}.
    • Modifier 59 should not be appended to the same claim line item as X{EPSU}

    Documentation is not required for a claim to be processed when modifier 59 or X{EPSU} is appended to a CPT/HCPCS code. However, if requested, the patient's medical records must legibly and accurately reflect the distinct procedural services that warranted the use of the modifier. Horizon BCBSNJ follows CPT coding rules and guidelines in requiring that documentation must support:
    • a different session or patient encounter
    • a different procedure or surgery
    • a different anatomical site or organ system
    • a separate incision/excision
    • a separate lesion
    • a separate injury

  2. Exceptions to Overrides : Horizon has determined that there are certain circumstances which are exempt from a modifier overriding an unbundling edit, or that there are circumstances in which appending modifier 59 or X{EPSU} to a code is inappropriate. The following is a list of some, but not all, of the circumstances in which appending a distinct procedural service modifier to a CPT/HCPCS code will not cause the override of the applicable edit, and will not allow for separate reimbursement:
    • Duplicate coding
    • Services and supplies specified in the Bundled Services and Supplies Rule within the ClaimsXten Editing Rules Policy
    • E & M or DME item codes
    • National Correct Coding Initiative (NCCI) edit code pairs with a 'superscript' of zero, or a modifier allowance indicator of zero.
    • When the denial of a code is supported by CPT parenthetical language that indicates a code is not reportable "with" specific other code(s) (e.g., do not report xxxxx with yyyyy...), distinct procedural service modifiers will not override the denial
    • Claims submitted for radiology services rendered to a patient enrolled in a plan/program that participates in our Radiology/Imaging Services program managed by eviCore healthcare.

In accordance with CMS National Correct Coding Initiative (NCCI) Procedure to Procedure (PTP) edit guidelines, Horizon shall consider for reimbursement a procedure or service that is distinct or independent from other services performed on the same day by the same provider when NCCI edit code pairs with a 'superscript' of zero, or a modifier allowance indicator of zero are appropriately appended with Modifiers 59 or X{EPSU} to the paid or denied code.

In addition to the services described in the Exceptions to Override, modifier 59 or X{EPSU}, Horizon BCBSNJ does not allow for separate reimbursement for the first code(s) listed below in the following code to code relationships.

Code below will be denied: Description When reported with the code(s) below:
29823¹ Shoulder Arthroscopy 29806, 29807, 29819, 29820, 29821, 29825
29862² Hip Arthroscopy 29914-29916
29863² Hip Arthroscopy 29914-29916
29870³ Knee Arthroscopy 29874, 29877
29875³ Knee Arthroscopy 29880-29881
29876³ Knee Arthroscopy 29880
29916² Hip Arthroscopy 29914-29915
31295⁴ Nasal/Sinus Endoscopy 31233, 31256, 31257
31296⁴ Nasal/Sinus Endoscopy 31276
31297⁴ Nasal/Sinus Endoscopy 31235, 31287, 31288
43280-43283¹ Laparoscopy 43770-43775
45378⁵ Colonoscopy 45380-45389
45381⁵ Colonoscopy 45382
45382⁵ Colonoscopy 45380, 45384, 45385, 45386, 45389
45384⁵ Colonoscopy 45385, 45388
45385⁵ Colonoscopy 45388
45386⁵ Colonoscopy 45388-45389
45388⁵ Colonoscopy 45385
63042¹ Laminotomy 22630, 22632, 22633, 22634
63047¹ Laminectomy 22630, 22632, 22633, 22634
76856¹ U/S Pelvic 93976

¹ Effective November 23, 2020.

² Formerly addressed in our Hip Arthroscopy reimbursement policy. This policy has been retired and its guidelines consolidated under this policy.

³ Formerly addressed in our Knee Arthroscopy reimbursement policy. This policy has been retired and its guidelines consolidated under this policy.

⁴ Formerly addressed in our Balloon Sinuplasty reimbursement policy. This policy has been retired and its guidelines consolidated under this policy.

⁵ Formerly addressed in our Colonoscopy with Mod 59 reimbursement policy. This policy has been retired and its guidelines consolidated under this policy.

Limitations and Exclusions:
While reimbursement is considered, payment determination is subject to, but not limited to:

  • Group or Individual benefit
  • Provider Participation Agreement
  • Routine claim editing logic, including but not limited to incidental or mutually exclusive logic, and medical necessity
  • Mandated or legislative required criteria will always supersede.

3/29/2009: Policy Approved

1/25/2017: Updated Procedure Section to include Appropriate/Inappropriate use for Modifiers X{E, P, S, U} and updated same for Modifier 59.

7/27/2020: Revised to consolidate several policies referencing Modifier 59, including: Balloon Sinuplasty; Colonoscopy with Modifier 59; Hip Arthroscopy; and Knee Arthroscopy. Effective 11/15/2020, Horizon BCBSNJ added additional code combinations (29823, 43280-43283, 63042, 63047, 76856) not eligible when billed with Modifiers 59, X{EPSU}.
4/27/2023: Added a new bullet to "3. Exceptions to Overrides" content within the Policy: section to clarify our approach to Modifiers 59, X{EPSU} when applied to codes for radiology services managed by eviCore.