MA121 Remark Code: X-Ray Date Missing or Invalid
MA121 means the x-ray date on the claim was missing, incomplete, or invalid. It is most often seen on chiropractic claims where an x-ray was used to demonstrate a spinal subluxation.
Quick facts
- Code
- MA121 (RARC MA121)
- Status
- Active In use since January 1, 1997; last modified December 2, 2004.
- Code set
- Remittance Advice Remark Codes (RARC)
- Group codes
-
- CO (Contractual Obligation): The service was not paid because the x-ray date was missing or invalid. The provider corrects it; the patient is not billed.
- Official description
Missing/incomplete/invalid x-ray date.
X12 Remittance Advice Remark Codes, retrieved September 25, 2026- Last verified
- against the official X12 list.
What MA121 means
MA121 tells you the x-ray date was missing, incomplete, or invalid on a claim that needed it. The most common scenario is chiropractic manipulation billed to Medicare, where the chiropractor documents a spinal subluxation. If the subluxation was demonstrated by x-ray, the date of that x-ray is reported on the claim.
It is a data defect, usually paired with CARC 16.
Common causes
- Item 19 was left blank on a chiropractic claim that relied on an x-ray.
- The date was put in the wrong field, such as item 14.
- The date is after the date of service, which is illogical.
- The electronic claim did not include the x-ray date qualifier.
How to fix it
- Check the record for the x-ray that documented the subluxation and its date.
- Enter the date in item 19 or the equivalent 837 date segment.
- Confirm the x-ray timing meets the payer’s requirements; otherwise expect M1.
- Resubmit the corrected claim.
How to prevent it
- Capture the x-ray date in the patient’s chiropractic profile at the start of the course of treatment.
- Require the date whenever the x-ray method is selected.
- A Claims Validator can flag chiropractic claims missing x-ray or treatment dates.
Codes that may appear with MA121
- CO-16 (Claim/service lacks information or has submission/billing error(s).): The claim is missing information needed for adjudication, specifically the x-ray date.
Related and easily confused codes
- MA122 (Missing/incomplete/invalid initial treatment date.): The initial treatment date, another date chiropractic claims often require.
- MA100 (Missing/incomplete/invalid date of current illness or symptoms.): The date of current illness or symptoms.
- M1 (X-ray not taken within the past 12 months or near enough to the start of treatment.): The x-ray was not taken recently enough relative to the start of treatment.
MA121 FAQ
Where is the x-ray date reported?
Medicare's CMS-1500 instructions direct chiropractors to put the x-ray date in item 19 when an x-ray was used to demonstrate subluxation. Electronically it is reported in the claim's date information.
Does Medicare require an x-ray for chiropractic care?
Not always. A subluxation may be demonstrated by x-ray or by physical examination. If an x-ray was used, its date is needed.
What is the difference between MA121 and M1?
MA121 means the x-ray date was missing or invalid. M1 means a date was present but the x-ray was not taken recently enough relative to treatment.