CO-29 Denial Code About Filing Limit Expired for Claim Submission

A CO-29 denial occurs when a claim is submitted after the payer’s allowed filing timeframe has passed. Every payer, including commercial plans, Medicare, Medicaid, and managed care organizations, sets specific deadlines for how long providers have to file claims after the date of service. When these deadlines are missed, the payer rejects the claim without payment. Filing-limit denials can significantly impact revenue, making timely submissions and strong claim-tracking processes essential for maintaining a clean and efficient billing workflow.

What CO-29 Means

A CO-29 denial indicates that the claim was submitted after the payer’s required filing timeframe, meaning the insurer will not process or reimburse the service because the submission deadline has expired. Filing limits vary among payers; some allow 90 days, others 120, 180, or up to 365 days. But all enforce these deadlines strictly. Even a single-day delay can cause a claim to be rejected. CO-29 denials often occur when claims are delayed due to documentation issues, incorrect payer submissions, internal workflow bottlenecks, or failure to track timely filing requirements.

Common Reasons for CO-29

Claim submitted after the payer’s filing deadline:

The most direct cause of CO-29 is simply submitting the claim after the allowable timeframe has passed. Whether due to overlooked dates, staff shortages, or delays in processing, the payer will deny any claim filed after its strict cutoff.

Delays caused by missing or late documentation:

When providers fail to complete documentation promptly or additional records are required, billing teams may lack the necessary information to code and submit the claim on time. These delays often cause submissions to be filed outside the filing window.

Incorrect insurance was billed first, causing timing issues:

If the claim is mistakenly sent to the wrong insurer, the time spent correcting the error can cause the filing limit for the correct payer to expire. This is especially common when patients have multiple coverage changes or unreported insurance updates.

Claim placed on hold due to missing information and resubmitted too late:

When a payer requests additional information or clarification, the claim is placed on hold. If the provider’s response is delayed, the claim may ultimately surpass the filing limit and be denied once resubmitted.

Corrections or adjustments submitted after the allowed timeframe:

Some payers enforce separate filing limits for corrected claims. If a correction or adjustment is submitted outside their designated window, the payer will reject it under CO-29.

Failure to monitor payer policy updates:

Payers occasionally modify their filing limits, and practices that are unaware of these changes may continue working off outdated timelines. This often results in unintended late submissions and preventable CO-29 denials.

Why CO-29 Denials Occur

CO-29 denials occur when the payer receives a claim after the allowable filing window has closed. These denials are often the result of internal workflow delays, missing information, or administrative errors that prevent timely submission. Understanding the underlying causes helps practices strengthen their processes and avoid preventable revenue loss.

Claim submitted past the payer’s filing window

Every payer has a strict timeline for claim submission. When a claim arrives after this deadline, whether 90, 120, 180, or 365 days, it is automatically denied with no payment responsibility on the payer’s side.

Incorrect insurance was billed first, causing delays

Submitting a claim to the wrong insurer, even once, can be a time-consuming process. By the time the error is discovered and corrected, the filing limit for the correct payer may have already expired.

Internal workflow delays in charge entry or documentation

Late coding, delayed provider documentation, or backlogged charge entry can cause claims to exceed the filing deadline. These workflow bottlenecks are among the most common contributors to CO-29 denials.

Claims held due to requests for additional information

If a payer requests more documentation and the provider does not respond quickly, the claim may exceed the timely filing deadline by the time it is resubmitted.

Corrected claims submitted after the adjustment window

Some payers require corrected or revised claims within a separate, shorter timeframe. Submitting a correction as a new claim or submitting it too late may result in a CO-29 denial.

Failure to track or update payer-specific filing limits

Filing deadlines vary widely, and if staff are unaware of each payer’s current limit, claims may be submitted late unintentionally. Failing to keep up with policy updates increases the risk of timely filing denials.

CMS & AAPC-Aligned Best Practices For Denial Code CO-29

Preventing CO-29 denials requires consistent monitoring of claim timelines, organized internal processes, and payer-specific awareness. By following the best practices below, healthcare organizations can reduce timely filing errors and maintain a smoother, more reliable revenue cycle.

Maintain a payer-specific filing limit reference list

Each payer has its own filing window, and staying current with these timelines helps billing teams avoid submitting bills late. Keeping this information accessible ensures that staff can quickly confirm deadlines before submitting claims.

Submit claims within 24–72 hours of service whenever possible

Faster claim submission minimizes the risk of delays caused by documentation, coding backlogs, or coverage verification issues. Early submission also provides room for corrections if needed.

Verify insurance upfront to avoid billing the wrong payer

Insurance errors lead to significant delays. Verifying active coverage and payer order at registration prevents claims from being sent to the wrong carrier and protects filing time for the correct payer.

Implement internal timelines for coding, documentation, and charge entry

Timely filing requires strong internal coordination. Assigning deadlines for provider documentation, coding completion, and charge entry ensures claims move through the workflow without unnecessary delays.

Use automated tools to flag claims nearing filing deadlines

Claim-tracking software and RCM tools can alert staff when claims approach cutoff dates. These automated reminders help prioritize urgent submissions and reduce the likelihood of expired filing windows.

Train staff on timely filing policies and denial trends

Education ensures that front-desk, coding, and billing teams understand payer-specific filing rules and know how to prevent common mistakes. Regular training supports compliance and reduces recurring CO-29 denials.

Corrective Action Steps For CO-29

When a CO-29 denial occurs, the goal is to determine whether the claim truly missed the filing limit or if supporting documentation can justify a timely submission. The steps below outline how to resolve the denial and prevent similar issues in the future.

Confirm the payer’s filing limit and compare it to the submission date

Review the insurer’s timely filing policy and the actual submission date. This helps determine whether the denial is valid or if the claim may still be eligible for reconsideration.

Request reconsideration if a payer error caused the delay

If the claim was originally submitted on time but delayed due to payer system issues, incorrect routing, or processing errors, request reconsideration with proof of timely submission.

Submit supporting documentation if timely filing proof exists

When claims were submitted on time but lack documentation, provide evidence such as clearinghouse receipts, acceptance reports, or submission logs to validate timely filing.

Correct insurance and submit to the proper payer if still within their deadline

If the claim was mistakenly billed to the wrong insurer, rebill the correct payer immediately. As long as their filing limit has not expired, the claim may still be payable.

Resubmit as a corrected claim when permitted

Some payers allow corrected claims even after the original filing window has closed, provided the initial claim was submitted on time. Use proper frequency codes when resubmitting corrections.

Document revised workflows to prevent future filing-limit breaches

Identify what caused the delay, internal workflow gaps, missing documentation, slow approvals, and update processes to ensure timely submission going forward.

BillingFreedom – Timely Filing Management & Clean Claim Support

BillingFreedom helps healthcare organizations prevent CO-29 denials by ensuring claims are submitted accurately and well within payer filing limits. Our team closely monitors claim timelines, verifies payer-specific deadlines, and utilizes automated tracking tools to alert staff before critical cutoff dates. 

We streamline documentation workflows, speed up coding and charge entry, and ensure claims move through the billing process without delay. With proactive oversight and real-time monitoring, BillingFreedom significantly reduces the risk of timely filing denials and improves overall claim acceptance rates.

Beyond timely filing management, BillingFreedom provides complete RCM support, including denial review, corrected claim submission, and detailed follow-up to recover revenue whenever possible. Our specialists work closely with providers and administrative staff to identify workflow bottlenecks, strengthen internal processes, and eliminate recurring filing-limit issues. By partnering with BillingFreedom, practices maintain a smoother claim cycle, fewer denials, and more consistent reimbursement.

For more details about our exceptional medical billing services, please don't hesitate to contact us via email at info@billingfreedom.com or call us at +1 (855) 415-3472.

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