N823: Incomplete/invalid procedure modifier(s)
A modifier was submitted on the claim line, but it is incomplete, invalid, or does not correctly apply to the procedure code and documentation.
Corrective actions
- 1
Review the modifier against documentation
Confirm the clinical record supports the modifier submitted, and check for simple entry errors such as a wrong digit or an outdated modifier.
- 2
Correct the modifier and resubmit
Replace the invalid modifier with the correct one and resubmit as a corrected claim, keeping supporting documentation on file in case of audit.
Usually paired with
Retrieved 2026-07-18.
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DenialPath provides billing and administrative guidance based on published CMS and X12 sources. It is not medical advice, not a coverage determination, and not a guarantee of payment. NCCI and MUE edits are republished quarterly and payer policies vary by contract. Always confirm against the payer's own current policy before submitting or appealing.