CARC 4 Denial Appeal

Modifier doesn't match the procedure code

The procedure code is inconsistent with the modifier used. Usage: Refer to the 835 Healthcare Policy Identification Segment (loop 2110 Service Payment Information REF), if present.

The winning argument

The modifier reported accurately describes how the service was delivered and is a valid combination under current coding guidance: CMS expressly permits behavioral and mental health services furnished by telehealth to a patient in their home — including audio-only technology where the patient cannot use or does not consent to video — billed with POS 02 or POS 10 and the applicable telehealth modifier. X12's own usage instruction for CARC 4 directs the payer to identify the specific healthcare policy relied upon in the 835 Healthcare Policy Identification Segment; if no policy was identified, demand the specific published policy or claim edit under which the billed procedure-modifier combination is inconsistent, and request reprocessing.

• The Consolidated Appropriations Act, 2021 permanently removed geographic and place-of-service restrictions for behavioral-health telehealth, and CMS confirms audio-only is permitted for behavioral-health services to a patient in their home — so a blanket edit rejecting valid telehealth modifier/POS combinations on psychotherapy codes misapplies current policy.
• Where the denial stems from a credential-level modifier (HO/HN), the modifier reported matches the rendering clinician's licensure/education level; state Medicaid manuals require these modifiers precisely to identify practitioner level, and a mismatch against the payer's credentialing file is a record-correction issue, not grounds to deny a correctly coded service.
• CARC 4's usage note obligates the payer to point to the specific policy in the 835 remittance (loop 2110 REF); a denial without an identifiable policy basis cannot be evaluated or corrected and should be reopened.
• If the payer's published policy in fact requires a different modifier for this service (e.g., GT rather than 95, or a missing level-of-care modifier), the appropriate remedy is acceptance of a corrected claim and reprocessing — please provide corrected-claim submission instructions.

Sample appeal letter body

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We are appealing the denial under CARC 4 (the procedure code is inconsistent with the modifier used) of CPT {{cpt_code}} ({{service_description}}) furnished on {{date_of_service}} for {{patient_reference}}. The claim was submitted with modifier {{modifier_billed}} and place of service {{place_of_service}}, which accurately reflect how the service was delivered and are consistent with current coding guidance: CMS guidance permits behavioral and mental health services to be furnished via telehealth to a patient in their home — including by audio-only technology where the patient cannot use or does not consent to video — with professional claims reported using POS 02 or POS 10 and the applicable telehealth modifier. The rendering clinician holds the {{clinician_credential}} credential corresponding to the practitioner-level modifier reported. We further note that X12's usage instruction for CARC 4 directs the payer to identify the specific healthcare policy relied upon in the 835 Healthcare Policy Identification Segment (loop 2110 REF), and the remittance advice we received did not identify such a policy. We therefore request that you either cite the specific published policy or claim edit under which modifier {{modifier_billed}} is inconsistent with CPT {{cpt_code}} on this date of service, or reprocess this claim for payment; if your policy requires a different modifier for this service, please advise so that we may submit a corrected claim promptly.