OA-29: Timely Filing Limit Expired

What Does OA-29 Mean?

OA-29 appears primarily in coordination of benefits situations where the secondary payer is denying a claim for timely filing. This typically occurs when the primary payer's adjudication took so long that the secondary filing window expired before the provider could submit. The OA designation signals that the financial responsibility does not fall cleanly on the provider or the patient — it depends on the specific COB arrangement and whether the delay was within the provider's control.

When CARC 29 appears on a remittance, the payer is telling you that the claim arrived after the allowed filing window closed. Every payer contract specifies a timely filing limit — Medicare allows 12 months from the date of service, most commercial plans allow 90 to 180 days, and Medicaid deadlines vary by state. Once that window shuts, the payer has no obligation to pay regardless of whether the service was medically necessary, properly coded, or otherwise clean.

This code overwhelmingly appears with Group Code CO, which means the provider absorbs the full financial hit. You cannot transfer a CO-29 balance to the patient because the denial stems from a provider-side administrative failure, not from a coverage limitation or patient responsibility issue. The only viable path to recovery is an appeal supported by concrete proof that the original submission occurred within the deadline — a clearinghouse acceptance report with a timestamp, a payer portal submission confirmation, or a certified mail receipt.

CARC 29 frequently surfaces as a secondary denial. A claim initially denied for a coding error or missing information sits in a work queue, and by the time staff correct and resubmit it, the filing window has lapsed. This cascading pattern makes CARC 29 one of the most preventable yet financially damaging denial codes in revenue cycle management. Practices that lack automated deadline tracking or that rely on manual follow-up processes are disproportionately affected.

Common Causes

How to Resolve

Determine whether you have proof of timely filing — if yes, appeal; if no, write off the balance and fix the workflow that caused the miss.

1. Document the primary payer's processing timeline Pull the primary payer's ERA and note the date of service, the date you submitted to the primary payer, and the date the primary payer adjudicated. This timeline demonstrates the delay was not caused by provider inaction.
2. Request a filing deadline exception from the secondary payer Contact the secondary payer and request an exception to their timely filing requirement. Provide the primary ERA as evidence that you could not file the secondary claim sooner. Many payers have COB exception processes that extend the filing window from the primary adjudication date.
3. Determine residual patient responsibility If the secondary payer denies the exception, evaluate whether the remaining balance should be billed to the patient or written off. Review the patient's benefits and your contractual obligations with both payers before making this determination.

How to Prevent OA-29

• Set up automated secondary claim generation triggered by primary ERA posting to eliminate manual handoff delays
• File secondary claims on the same day you receive the primary ERA — do not batch them for weekly or monthly submission
• Track primary payer processing times and escalate any primary claim that has been pending for more than 60 days, especially if the secondary payer has a short filing window

General Prevention

• File secondary claims immediately upon receipt of the primary payer's ERA rather than batching them for later submission
• Set up automated secondary claim submission triggered by primary ERA posting to eliminate manual delays in COB scenarios
• Track primary payer adjudication timelines and proactively contact slow-processing primary payers to expedite adjudication before secondary filing deadlines approach

Also Filed As

The same CARC 29 may appear with different Group Codes:

Related Denial Codes