CARC 181

Narrative 
Procedure code was invalid on the date of service.

RARC M20

Narrative 
Missing/incomplete/invalid HCPCS.

Reason for Non-Coverage

• The procedure code billed is not valid for the date of service or the procedure code is not recognized by Medicare.

Claim Denial vs. Rejection
Rejection.

Appeal Rights
No.

Patient Responsibility
No.

Reference/Educational Material

• CMS IOM Publication 100-4, CH 26. Section 10.1 and 10.4, (Subsection 24D) (PDF, 611 KB)
• CMS IOM Publication 100-4, Ch 23, Sec 30.2.2 (PDF, 1 MB)

Resolution
Identify the CPT^® or HCPCS code that was effective on the date of service billed and that the code is recognized by Medicare. If it is different from the previously billed code, submit a new claim with the correct code. For example, verify the Medicare Physician Fee Schedule Data Base status indicator of the procedure code to ensure that procedure is valid for Medicare purposes.