OA-85: Patient Interest Adjustment

What Does OA-85 Mean?

When paired with Group Code OA, CARC 85 (Patient Interest Adjustment) is processed as an adjustment outside the standard CO/PR classifications. This typically occurs in secondary payer or coordination of benefits scenarios. Review the remittance details and the COB arrangement to determine financial responsibility and appropriate next steps.

CARC 85 appears on a remittance when the payer adjusts payment for the patient interest adjustment. This is a standard plan-defined cost-sharing amount that the patient is obligated to pay per their insurance benefits. The code confirms the payer processed the claim correctly and applied the plan's benefit structure as designed.

Common scenarios that trigger this adjustment include: the payer delayed processing or payment beyond contractual or regulatory timeframes, resulting in interest charges that accrue on the patient's account as part of the overall balance adjustment; The patient failed to make timely payments on their balance according to the agreed-upon payment plan or terms, and interest charges were applied to the outstanding amount; A denied claim made the patient responsible for the full charge, and interest accrued during the time between the denial and patient notification or payment. The group code paired with CARC 85 determines who bears the financial responsibility — PR shifts it to the patient, CO places it on the provider as a contractual obligation, OA indicates a coordination of benefits or other payer adjustment.

Common Causes

How to Resolve

1. Review the coordination of benefits Examine the OA-85 adjustment to understand how it fits within the primary/secondary payer relationship or other multi-payer context.
2. Verify primary payer adjudication Review the primary payer's EOB to understand the basis for the secondary payer's OA adjustment.
3. Determine the responsible party Based on the COB review, identify whether the adjustment should be absorbed, billed to another payer, or if additional documentation is needed.
4. Appeal or resubmit if needed If the interest payment does not match state prompt-pay law requirements or your contractual terms, contact the payer with documentation of the correct interest calculation. Include the original claim payment date, the required payment timeframe, and the applicable interest rate.
5. Follow up Monitor the claim status and take additional action as needed based on the COB determination.

How to Prevent OA-85

• Track interest payments alongside claim payments to ensure correct posting in the practice management system
• Verify that interest amounts match state prompt-pay law requirements and payer contract terms
• Monitor delayed payment patterns by payer to identify systemic late-payment issues that trigger interest adjustments

Also Filed As

The same CARC 85 may appear with different Group Codes:

Related Denial Codes