Skip to main content

N458 Remark Code: Incomplete or Invalid Diagnostic Report

N458 means the diagnostic report was incomplete or invalid. The payer received a report, but it was missing findings or an impression, was unsigned or preliminary, did not match the billed study, or otherwise could not support the claim.

Quick facts

Code
N458 (RARC N458)
Status
Active In use since July 1, 2008.
Code set
Remittance Advice Remark Codes (RARC)
Group codes
  • CO (Contractual Obligation): Payment waits on a usable report. The provider corrects or completes it; the patient is not billed.
Official description
Incomplete/invalid Diagnostic Report.
X12 Remittance Advice Remark Codes, retrieved September 25, 2026
Last verified
against the official X12 list.

What N458 means

N458 means the payer has a diagnostic report but will not rely on it. Payers reviewing a study or its interpretation usually check that the report is final, signed, for the right patient and date, and complete enough to show what was done and found. If it fails any of those checks, the claim comes back with N458, typically paired with CARC 251.

Problems reviewers find

  • Preliminary status. A draft or preliminary read was sent instead of the final report.
  • No signature from the interpreting provider, or no date.
  • Missing sections. The report lacks findings, an impression, or a description of the study performed.
  • Mismatch with the claim. The report describes a different study, body part, number of views, or laterality than the billed code.
  • Wrong patient or date.
  • Illegible or partial copy.

How to fix it

  1. Compare the report you sent against the billed service, line by line: study type, laterality, date, and patient.
  2. Get the final signed version from the reading provider or facility if what you sent was preliminary.
  3. Address content gaps through a dated addendum by the interpreting provider, only if it reflects what was actually done.
  4. Correct the claim if the report is accurate and the billed code was wrong, and submit a corrected claim with resubmission code 7.
  5. Resend with a cover sheet that lists the claim number and what changed.

How to prevent it

Release only final, signed reports to payers. For interpretation billing, hold the charge until the report is finalized and verify that the billed code matches what the report describes. Coding reviews that compare report language with billed codes catch many mismatches before submission.

Codes that may appear with N458

  • CO-251 (The attachment/other documentation that was received was incomplete or deficient.): The documentation received was incomplete or deficient.
  • CO-250 (The attachment/other documentation that was received was the incorrect attachment/document.): The wrong document was received, and the needed report is still missing.
  • N457 (Missing Diagnostic Report.): No diagnostic report was received.
  • N396 (Incomplete/invalid laboratory report.): A laboratory report was incomplete or invalid.
  • N468 (Incomplete/invalid Report of Tests and Analysis Report.): A tests and analysis report was incomplete or invalid.

N458 FAQ

What is the difference between N457 and N458?

N457 means no report arrived. N458 means a report arrived but it could not be used as sent.

Can the reading provider amend the report?

Yes, through a properly dated addendum. The original report should remain intact.

What if the report is for a different study than billed?

Determine which is correct. If the claim is wrong, submit a corrected claim. If the wrong report was sent, send the right one.