CARC 2: Coinsurance Amount

What it means

This code indicates that part of the claim amount was not paid by the payer because it is the patient's responsibility as coinsurance, which is the percentage of the allowed amount the patient owes after any deductible has been met.

Common causes

• The patient's health plan requires a coinsurance percentage (e.g., 20%) after the deductible is satisfied.
• The claim was processed correctly and the payer is applying the standard coinsurance split per the patient's benefit plan.
• The coinsurance amount shown may be bundled with other adjustment codes on the same claim line (e.g., deductible or copay).
• Secondary insurance or supplemental coverage may be expected to cover this coinsurance amount.

How to fix it

1. Verify the coinsurance percentage and amount against the patient's benefit summary or the payer's remittance advice (ERA/EOB).
2. Confirm the allowed amount and that the coinsurance calculation matches the plan terms.
3. Bill the patient directly for the coinsurance amount if no secondary payer applies.
4. If the patient has secondary or supplemental insurance, submit the claim to that payer referencing this coinsurance amount.
5. Check for accompanying remark codes (RARCs) that may provide additional detail on how the amount was calculated.

Appeal / resubmit

Coinsurance amounts are typically a normal part of claim adjudication rather than a denial, so there is usually nothing to appeal to the payer. If you believe the coinsurance was calculated incorrectly, review the patient's plan documents and the allowed amount, then contact the payer to request a recalculation review, providing documentation such as the benefit summary or prior EOBs.

Related codes

• 1
• 3
• 45

Frequently asked

More free billing tools: all denial codes · denial lookup · Medicare fee calculator

This content is for informational purposes only and does not constitute billing or legal advice. Always verify with the specific payer and current coding guidelines.