CO-16 Denial Code: Claim/service lacks information or has submission/billing error(s)
The catch-all administrative denial: the payer says something on the claim is missing, malformed, or inconsistent — a data problem, not a coverage decision.
Why it happens
- Missing or invalid patient/subscriber data (DOB, member ID, name mismatch)
- Missing referring/ordering provider NPI or taxonomy
- Blank or malformed required fields (accident info, onset date, place of service)
- Attachments the payer expected but never received
How to fix it, step by step
- Read the companion RARC remark code on the remittance — it usually names the exact missing field
- Correct the identified field in your PM system
- Resubmit as a corrected claim (not an appeal — corrected-claim channel is faster)
- Track the payer's resubmission window; most allow 90+ days from the original denial
Is it worth working?
Very high. CO-16 denials are correctable paperwork, not coverage decisions — most pay on clean resubmission within 2–4 weeks.
Very high. CO-16 denials are correctable paperwork, not coverage decisions — most pay on clean resubmission within 2–4 weeks.
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.