CurrentUnitedHealthcarePolicy N/A

Add-on CPT/HCPCS code reimbursement

This UnitedHealthcare Community Plan reimbursement policy governs when add-on procedure codes are reimbursable in Medicaid products and how they must be reported by physicians and other qualified health care professionals.

Policy Summary

PayerUnitedHealthcare

PolicyAdd-on CPT/HCPCS code reimbursement

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateN/A

Next Review DateN/A

Key ActionReport add-on codes only in addition to the appropriate primary service by the same individual or as allowed by group/specialty rules; stand-alone add-on codes are not reimbursable.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

Medicaidproducts governed

+99292, +17312, +96121example add-on codes mentioned

Multiple (e.g., NC)state exceptions present

Add-On Listattachment exists

When Add-On Codes Are Covered

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Add-on code must be reported in addition to an appropriate primary service code and is not reimbursable as a stand-alone code.

Add-on procedures must be reported with the primary procedure on the same date of service unless otherwise specified within this policy.

See exceptions for certain codes (e.g., Mohs, psychological testing) that may be billed on the same claim even if dates differ.

Add-on and primary should be reported by the Same Individual Physician or Other Qualified Health Care Professional reporting the same Federal Tax Identification Number, unless policy specifies alternate group/specialty reporting rules.

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Exceptions / special handling

Certain add-on codes (for example, Mohs surgery add-ons and psychological testing add-ons) may be performed on different dates but should be reported on the same claim as the primary procedure per policy guidance.
When CPT/CMS do not definitively list primary/add-on pairs, UnitedHealthcare will interpret CPT, CMS, and specialty society guidance to establish required primary/add-on relationships and require reporting consistent with that interpretation.

Providers must follow the Add-On to Primary Code Relationship List attachment to determine codes reimbursable only when reported with the appropriate primary code.

Examples and Coding Details

Example primary and add-on codes referencedCPT

99291	Critical care initial 30-74 minutes (time-based primary)
+99292	Critical care add-on for each additional 30 minutes beyond initial 30-74 minutes (primary 99291)
17311	Mohs micrographic surgery primary example
+17312	Mohs add-on example
96136	Psychological/Neuropsychological testing primary example
+96137	Psychological testing add-on example

Critical care time threshold

Initial critical care timeCPT 99291: reported for the first 30–74 minutes of critical care

Additional critical care timeCPT +99292: reported for each additional 30 minutes beyond the first 74 minutes

When +99292 is reimbursableReimbursed when the Same Individual Physician/Other Qualified Health Care Professional provides more than 74 minutes of critical care

Same-specialty/group reporting optionSame Specialty clinicians may report +99292 when one reports the initial 99291 and others provide additional minutes, or a single physician may report on behalf of the group/same specialty

Separate reporting by different specialtiesPhysicians of different specialties within the same group report their own 99291 and +99292 based on time each provided

Billing and Reporting Requirements for Providers

Billing Rule

Add-on reporting requirements

Add-on codes are reimbursable only when reported in addition to the appropriate primary service by the Same Individual Physician or Other Qualified Health Care Professional reporting the same Federal Tax Identification Number on the same date of service, unless otherwise specified in this policy. Add-on codes reported as stand-alone services are not reimbursable per CPT and CMS guidelines. For this policy, the Same Individual Physician or Other Qualified Health Care Professional is the same individual rendering services and reporting the same Federal Tax Identification Number.

Documentation Required

Date-of-service and time-based add-on handling

Some add-on codes may be reported on the same claim as the primary procedure even when the actual dates of service differ — follow the guidance below for common time- or date-sensitive add-ons and report per the applicable CPT/CMS guidance and UnitedHealthcare interpretation.

Mohs micrographic surgery (+17312, +17314, +17315): These add-on codes may be performed on a different date than the primary Mohs procedure (17311, 17313). Consistent with CPT guidance, report the add-on on the same claim as the primary Mohs procedure even if dates differ.
Psychological/Neuropsychological testing (+96121, +96137, +96139): When test administration/scoring extends beyond the initial date, report the add-on on the same claim as the primary testing code even if dates differ.
Critical care (+99292): 99291 covers the first 30–74 minutes; +99292 is reported for each additional 30 minutes beyond the first 74. Reimbursement for +99292 is allowed when the Same Individual Physician/Other Qualified Health Care Professional provides more than 74 minutes. When multiple physicians of the same specialty or group provide critical care on the same date, either the clinician who furnished the first 30–74 minutes reports 99291 and others report +99292 for additional time they personally provided, or one physician may report on behalf of group members within the same specialty. Physicians from different specialties each report their own critical care services separately.
Note: Add-on codes are never reimbursed unless a primary procedure code is also reimbursed, and some add-on relationships require interpretation from definitive sources (CPT, CMS, specialty societies); UnitedHealthcare will identify and apply those primary/add-on relationships as needed.

Key Definitions

Add-on code

DefinitionAn add-on code identifies additional intra-service work associated with a primary procedure and is reported only in addition to the appropriate primary service per CPT/CMS guidance

NotationMany add-on codes are designated by a leading '+' in CPT and are listed in CPT Appendix D

Reimbursement ruleAdd-on codes are never reimbursed as stand-alone codes and must be reported with the appropriate primary procedure unless the policy specifies otherwise

Same Individual Physician or Other Qualified Health Care Professional

DefinitionThe Same Individual Physician or Other Qualified Health Care Professional is the same individual rendering health care services reporting the same Federal Tax Identification Number

Reporting implicationAdd-on and primary services should be reported by this same individual on the same date of service unless the policy specifies otherwise

Source contextUsed throughout the policy to require that add-on codes be reported in addition to the primary service by the Same Individual Physician or Other Qualified Health Care Professional

Same Group Physician or Other Qualified Health Care Professional

DefinitionSame Group Physician and/or Other Qualified Health Care Professional: all physicians and/or other qualified health care professionals of the same group reporting the same Federal Tax Identification Number

Group reporting optionsA single physician may report critical care service codes on behalf of other members within the same group/same specialty

Individual reporting when specialties differWhen group members are of different specialties, each reports their own critical care services separately (each may report 99291 and +99292 as appropriate)

Definitive Source

DefinitionDefinitive Source: a source that specifies exact codes, modifiers, or very specific instructions identifying required primary/add-on pairs (used when CPT/CMS explicitly list pairings)

Examples of contentMay include explicit code pair lists or directives within CPT, CMS, or other authoritative coding edits that identify required primary procedures for an add-on code

UsageWhen a Definitive Source exists, UnitedHealthcare requires the add-on be reported with the specified primary code(s)

Interpretive Source

DefinitionInterpretive Source: guidance that includes guidelines but does not list exact codes or modifiers, requiring interpretation to determine which codes correlate to the guidance

ApplicationUnitedHealthcare will interpret CPT, CMS, and specialty society guidance when definitive pairings are not specified to identify primary/add-on relationships

Implication for providersWhen interpretation is applied, the add-on code must still be reported with the identified primary procedure and is not reimbursed as a stand-alone code