What is the CO 29 Denial Code? 


At its essence, the CO 29 Denial Code indicates that the submission of a claim has exceeded the stipulated timeframe set by the insurance company. The error message typically reads: "The time limit for filing has expired." 

In practical terms, this means that the healthcare service provider has sent a billing claim past the deadline dictated by their agreement with the insurer. If a physician submits a claim after this agreed-upon period, the insurance company will reject the claim, using the CO 29 code to identify the reason. 

At the heart of this code lies the principle of "Timely Submission." These guidelines are a product of contracts between healthcare providers and insurance entities, dictating specific windows for claim submission. For instance, if a healthcare provider sends a claim 120 days after service when the insurance agreement allows only up to 90 days, the CO 29 code will be applied, leading to a denied claim. 

Common Reasons for CO 29 Denial 

  • Claim Submission Delays: The primary reason for receiving a CO 29 denial is that the claim was submitted after the designated timeframe set by the insurance company. 
  • Lack of Updated Fee Schedules: Medical providers sometimes neglect to update their fee schedules, which can inadvertently lead to late submissions. 
  • Unverified Patient Eligibility: If patient eligibility and benefits aren't verified before providing the service, it can cause delays and subsequent late filings.
  • Duplicate Claims: Another potential trigger is submitting a claim more than once for identical services, leading to a duplicate claim. This can be due to not receiving claim submission confirmations, not checking claim statuses before re-submission, or using varied billing data for the same service. 

Strategies to Address CO 29 Denials 

  • Review Submission Dates: As soon as you encounter a CO 29 denial, check when the insurance received the initial claim. Calculate the interval between the service date and the submission date to ensure compliance with the insurer's filing limit.
  • Proof of Timely Filing (POTF): Always maintain clear records that can act as evidence of timely filing. For instance, an EOB from a secondary insurance indicating that the primary insurance denied a claim can be used as POTF to appeal a denial from the secondary insurer. 
  • Engage with the Insurance Claims Department: Engaging proactively with the insurance claims department can often provide clarity on denial reasons. Inquiring about the claim's received date, denial date, and the stipulated timeframe for submission can provide actionable insights.
  • Appeal with Evidence: If you have evidence supporting timely filing, appeal the decision. Be ready with relevant documentation, like a copy of the claim and any associated POTFs. 

Preventing Future CO 29 Denials 

  • Stay Updated on Filing Limits: Familiarize yourself with the filing timeframes of all the insurance companies you deal with.
  • Use Clearinghouse Services: Employ clearinghouse services to inspect your claims prior to submission. These services can pinpoint errors, discrepancies, and confirm the timely filing, reducing the chances of CO-29 denials.
  • Prompt Documentation: Ensure services are documented promptly and that all necessary details are recorded accurately.
  • Regularly Review Claim Status: Constantly check the status of submitted claims to ensure they are not pending or misplaced within the system. 


Questions? Want us to review your data for free?

We’re here to answer any questions you have about PUREDI.