How do I resolve a CO-29 denial?

Verify the claim's original submission date from your clearinghouse's transmission report or 999 acknowledgment. Compare the submission date to the payer's timely filing deadline (from your contract or provider manual). If the claim was submitted on time: gather the clearinghouse submission confirmation (277CA or batch report) and appeal, citing the timely submission proof. If there was a payer-side issue (system outage, payer error): appeal citing the payer's own timely filing exception policy for system failures. If you missed the deadline: check whether the delay was due to a coordination of benefits (COB) situation — primary payer EOB is typically required before secondary claims, and most payers extend the TFL for COB. Document all future claims with submission confirmation numbers at the time of submission to prevent future TFL denials.

Can I appeal a CO-29 denial?

Yes. CO-29 denials are typically appealable with a 32% success rate. Resolution difficulty is Hard and typically takes 21-60 days.

835 Denial Combination

CO-29

Contractual Obligation · Claim-Level Adjustment

What This Combination Means

Timely filing denial — the claim was received outside the payer's required filing window. This is one of the most difficult denials to overturn because payers have contractual and regulatory authority to deny late claims. Success depends on proving the claim was submitted on time or that a valid exception applies.

32%

Appeal Success

21-60 days

Avg. Resolution

Hard

Difficulty

Yes

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-29 combination — not generic advice.

1
Verify the claim's original submission date from your clearinghouse's transmission report or 999 acknowledgment.
2
Compare the submission date to the payer's timely filing deadline (from your contract or provider manual).
3
If the claim was submitted on time: gather the clearinghouse submission confirmation (277CA or batch report) and appeal, citing the timely submission proof.
4
If there was a payer-side issue (system outage, payer error): appeal citing the payer's own timely filing exception policy for system failures.
5
If you missed the deadline: check whether the delay was due to a coordination of benefits (COB) situation — primary payer EOB is typically required before secondary claims, and most payers extend the TFL for COB.
6
Document all future claims with submission confirmation numbers at the time of submission to prevent future TFL denials.

Specialty Context

How CO-29 typically presents across different practice types.

Dental

Most dental plans require submission within 12 months of date of service. Coordinate with the front desk to ensure claims are batched and submitted within 30 days of service.

Medical

Medicare requires submission within 12 months of the date of service. Commercial payers vary from 90 days to 24 months. Check your contract or provider manual for the specific filing limit.

Behavioral Health

Session notes and claim submission must be completed in a timely fashion. Many behavioral health payers have 180-day filing limits, which is especially tight for retroactive billing adjustments.

Individual Code References

View the standalone definition for each code in this combination.

CARC 29

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