835 Denial Combination

CO-45

CO

Contractual Obligation · Service-Line Level Adjustment

What This Combination Means

A contractual write-off — the amount exceeds the fee schedule maximum allowable. This is expected and correct for in-network providers under a contract. The CO-45 amount is not billable to the patient. No appeal is needed unless the allowed amount appears incorrect relative to the current contract.

N/A

Appeal Success

1-3 days

Avg. Resolution

Easy

Difficulty

No

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-45 combination — not generic advice.

  1. 1

    Verify the write-off amount is correct by comparing to your current contracted fee schedule.

  2. 2

    Confirm the patient's cost share (deductible/copay/coinsurance) is applied correctly — CO-45 does not shift responsibility to the patient.

  3. 3

    If the allowed amount appears lower than your contract rate, pull your current fee schedule addendum and compare.

  4. 4

    If a discrepancy exists, file a contract compliance dispute (not a clinical appeal) with the payer's provider relations department.

  5. 5

    Post the adjustment in your practice management system and send the patient statement for their applicable cost share only.

Specialty Context

How CO-45 typically presents across different practice types.

Dental

Verify the allowed amount against your current Delta/Cigna/United Concordia fee schedule. If the allowed amount differs from your contract, request a fee schedule review.

Medical

CO-45 write-offs should match your contract exactly. If the allowed amount is lower than expected, compare to the current CMS fee schedule (for Medicare) or request your payer contract addendum.

Behavioral Health

Confirm the allowed amount against your behavioral health carve-out contract. Some managed behavioral health organizations (MBHOs) use a different fee schedule than the medical plan.

Individual Code References

View the standalone definition for each code in this combination.

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