835 Denial Combination

CO-16+N339

CO

Contractual Obligation · Claim-Level Adjustment

Missing Information

What This Combination Means

The claim was denied because it is missing, contains incomplete, or has an invalid similar illness or symptom date. This date field is required by the payer for adjudication but was either omitted from the claim or submitted incorrectly. Under the provider's contract, this amount must be written off and cannot be billed to the patient.

Financial Responsibility

provider writeoff

The provider must write off the denied amount due to contractual obligation. The patient cannot be billed for this billing error.

N/A

Appeal Success

7-14 days (corrected claim)

Avg. Resolution

Medium

Difficulty

No

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-16+N339 combination — not generic advice.

Not Appealable:This is a billing error for missing information that requires claim correction and resubmission rather than appeal.
  1. 1

    Identify the similar illness or symptom date requirement

    Review payer guidelines to determine which field (e.g., Box 11 on CMS-1500, loop 2300 DTP segment in 837) should contain the similar illness or symptom date and the required format.

  2. 2

    Obtain or verify the similar illness or symptom date

    Access clinical documentation or patient records to retrieve the date when similar symptoms or related illness first occurred, ensuring it is accurate and complete.

  3. 3

    Submit a corrected claim with the complete similar illness or symptom date

    Include the validated date in the appropriate field using claim frequency code 7 and track for timely adjudication.

Specialty Context

How CO-16+N339 typically presents across different practice types.

Dental

Medical

Similar illness or symptom date is commonly required for claims involving chronic conditions, follow-up care, or when establishing the onset of a new condition versus continuation of existing illness. This date helps payers assess medical necessity and coordinate benefits.

Behavioral Health

May be required for ongoing mental health or substance use treatment to establish when symptoms first appeared, particularly for continuing care claims or when differentiating between new episodes and relapses of chronic conditions.

Individual Code References

View the standalone definition for each code in this combination.

CARC 16RARC N339

Medicare Contractor Guidance for CARC 16

FCSO + Noridian + uhc + aetna + bcbs_az

This RUC is received when a claim is submitted with missing, incorrect, or invalid information. For details pertaining to your claim, please refer to the remittance advice remark codes (RARCs) on the remittance advice (RA).

How to Prevent CARC 16 Denials

  • ✓

    Review the RARC on the remittance advice to identify which specific field has the error.

  • ✓

    Per Medicare guidelines, claims must be filed no later than 12 months after the date of service. RUCs are not considered filed/submitted.

CMS guidelines for completion of form CMS-1500 in the Medicare Claims Processing Manual (100-04), Chapter 26SPOTFee Schedule Lookup ToolCMS laboratory demographics lookupModifier lookup toolNoridian Medicare PortalNMPIVRSame or SimilarPECOSPDAC

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Synthesized from official definitions — not from training data

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