The time limit for filing has expired

Why this happens on dental claims

• Claims stuck in clearinghouse rejection queues that nobody worked, discovered months later
• Secondary claims filed late because the primary explanation of benefits took months to arrive
• Coordination of benefits and eligibility fixes that consumed the filing window before a clean claim ever reached the payer

How to appeal CO-29

1. Pull proof of timely original submission: clearinghouse acceptance reports, 277CA acknowledgments, or certified mail records
2. Appeal with that proof; timely filing denials are routinely overturned when the original submission date is documented
3. For secondary claims, cite the primary adjudication date and the plan rule that measures the window from it
4. If no proof exists, check whether the plan allows good-cause exceptions and document what happened honestly
5. Fix the workflow gap that let the claim age out, or the same denial will recur

How to prevent it

• Work clearinghouse rejections daily, because a rejected claim was never received and the filing clock keeps running
• Track secondary filing deadlines from the primary remittance date in your PMS