CARC 1 Active

CO-1: Deductible Amount

TL;DR

The deductible was applied as a contractual adjustment. Review whether this should be patient responsibility instead.

Action
Review & Decide
Who Pays
Provider
Appeal
No
Patient Impact
None
Disclaimer
This content is for informational purposes only and does not constitute professional billing advice. Always verify information against your payer contracts and current coding guidelines. Consult a certified billing specialist for specific claim issues.

What Does CO-1 Mean?

With CO (Contractual Obligation), the deductible amount is treated as a contractual adjustment rather than a patient obligation. This is unusual for CARC 1 and may indicate a processing anomaly or a specific contract provision. Review the remittance carefully — if this should have been PR, contact the payer to request a correction.

CARC 1 appears on a remittance when the payer reduces payment because the patient has not yet satisfied their annual deductible. The deductible is the dollar amount a patient must pay out-of-pocket each plan year before the insurance plan begins covering services. Until that threshold is met, the full allowed amount (or a portion of it) is shifted to the patient.

This adjustment is especially common early in the calendar year when deductibles reset, and for patients enrolled in high-deductible health plans (HDHPs) where the deductible can exceed several thousand dollars. The code itself is not a denial — it confirms that the payer processed the claim correctly and applied the patient's plan benefits as designed.

How to Resolve

  1. Review the remittance for accuracy Check whether the CO group code was applied correctly. CARC 1 is almost always PR since deductibles are patient responsibility.
  2. Contact the payer if CO appears incorrect If the adjustment should be PR (patient responsibility), contact the payer to request a corrected remittance.
  3. Determine if a contract provision applies In rare cases, specific contract terms may designate a deductible amount as a contractual adjustment. Review your provider agreement.
  4. Appeal if needed If the CO designation is incorrect and the payer will not correct it, submit a formal appeal with documentation supporting the proper group code assignment.
Do Not Appeal This Code

Deductible Amount represents an amount the patient owes per their plan benefits — usually a deductible, coinsurance, or copay calculated against plan terms. Since the calculation comes from the benefits rather than a coverage denial, appeals don't apply. Verify the calculation against the patient's plan and collect the patient portion.

How to Prevent CO-1

Also Filed As

The same CARC 1 may appear with different Group Codes:

PR-1 OA-1

Related Denial Codes

CO-2 — Coinsurance Amount CO-66 — Blood Deductible CO-247 — Deductible for Professional Service in Institutional Setting CO-248 — Coinsurance for Professional Service in Institutional Setting CO-281 — Deductible Waived Per Contractual Agreement

Sources

  1. https://x12.org/codes/claim-adjustment-reason-codes
  2. https://revenuecyclemgmt.com/claim-adjustment-reason-codes/
  3. https://www.rivethealth.com/blog/carcs-rarcs-claim-adjustment-remittance-advice-codes
  4. https://www.aapc.com/resources
  5. Codes maintained by X12. Visit x12.org for official definitions.