OakClaim
N598N-series (general use)COB & Secondary

N598: Other health coverage is primary

The payer's records show different coverage as primary — you billed the secondary first.

Commonly appears with these denial codes

CO-22PR-22

The denial code gives the category; N598 pinpoints the specific problem. Read them together before touching the claim.

What to do about it

Verify coverage order with the patient and both payers, bill the true primary, then submit secondary with the primary's EOB. Update COB records at the front desk.

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More COB & Secondary remark codes