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CO-31
Recoverability: High
Patient cannot be identified as our insured
The payer cannot match the patient on the claim to a covered member. This is usually a data problem: wrong subscriber ID, misspelled name, wrong date of birth, or the wrong payer entirely.
Why this happens on dental claims
- Dependents indexed under the subscriber but submitted under their own details, including stepchildren and name changes that do not match enrollment
- Old subscriber IDs used after an employer changed plans or the payer reissued cards
- Claims sent to the wrong regional plan or payer ID when employers use lookalike network brands
How to appeal CO-31
- Re-verify eligibility with the current physical or digital card, confirming subscriber ID, subscriber name, patient date of birth, and payer ID
- Correct the demographic mismatch and resubmit; most of these denials die on a corrected claim
- If the patient truly is not on file, ask the subscriber's benefits administrator to confirm enrollment was transmitted
- Keep proof of the original submission date to defeat any later timely filing denial
How to prevent it
- Capture the current insurance card at every visit and verify electronically before the patient is seated
- Enter dependents exactly as the payer's eligibility response spells them
Related codes
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