CO-22 Denial Code: Care may be covered by another payer per coordination of benefits
The payer believes it isn't primary — another insurer should pay first. COB data goes stale constantly; this denial is routine and routinely fixable.
Why it happens
- Patient's other coverage terminated but this payer's COB file is stale
- Claim genuinely sent to secondary before primary adjudicated
- Medicare Secondary Payer questionnaire answers routed the claim wrong
- Patient never updated COB after a job/coverage change
How to fix it, step by step
- Have the patient call the payer to update COB (payers often require it from the member — give the patient a 2-line script)
- Verify actual primacy: employment coverage, Medicare rules, birthday rule for dependents
- If this payer IS primary: resubmit after the COB file updates
- If secondary: bill primary first, then resubmit with the primary EOB attached
Is it worth working?
High — COB denials are administrative loops; money arrives once the file is straightened out.
High — COB denials are administrative loops; money arrives once the file is straightened out.
How much is your practice writing off to denials like this?
Send 6 months of remittance files (3 clicks in your billing software) — get a free one-page scorecard of your denied dollars, what's recoverable, and your top payer patterns — within one business day of receiving your files. Recovery is contingency-only: no fee unless money posts.
Get the free denial auditMore codes: the Claimmender denial-code library.