M51
RARC (Medicare)
Procedure code missing or invalid
The CPT or HCPCS code on the line is missing, invalid for the date of service, or incomplete.
Usual causes
- Deleted CPT code after the yearly update.
- Typo or a code with a missing digit.
- Category II or III code the payer does not accept.
The fix
Replace the code with the valid one for the date of service and resubmit.
Appeal or corrected claim?
Corrected claim
Corrected claim.
Deadline to watch
Timely filing limit.
Exact limits are in your payer contract or provider manual. When in doubt, send the correction or appeal this week.
Questions
M51 in short
What does M51 mean?
The CPT or HCPCS code on the line is missing, invalid for the date of service, or incomplete. The official X12 text reads: "Missing/incomplete/invalid procedure code(s)."
What usually causes a M51 denial?
Deleted CPT code after the yearly update. Typo or a code with a missing digit. Category II or III code the payer does not accept.
How do I fix M51?
Replace the code with the valid one for the date of service and resubmit.
Should I appeal M51 or send a corrected claim?
Corrected claim. Corrected claim.
What deadline applies to M51?
Timely filing limit.