RARC M16: See Payer Website, Mailings, or Bulletins for Policy Details
RARC M16 is an Alert code: "Please see our web site, mailings, or bulletins for more details concerning this policy/procedure/decision." It requires no rework by itself — it points you to a published payer policy that explains the adjustment on the line, usually one that recently changed.
- Type
- Alert (informational only)
- Usually paired with
- CO-96, CO-45, or any policy-driven CARC
- Fixable?
- Not directly — the CARC on the line is the work item
- Typical fix
- Pull the cited policy; act on the CARC accordingly
What does remark code M16 mean?
Official X12 text: "Alert: Please see our web site, mailings, or bulletins for more details concerning this policy/procedure/decision." It is the payer saying "we explained this somewhere else." M16 carries no dollars and no field to fix; it is a pointer to a published policy behind whatever the CARC did to the line.
ERA mini-example: 81003 (urinalysis) billed $12.00 pays $0.00 with CO-96 and M16 — the payer moved point-of-care urinalysis to non-covered under a lab policy updated last quarter. The CO-96 is the denial; M16 tells you a bulletin explains why.
Which denial code does M16 come with?
Anything policy-driven: CO-96 (non-covered), CO-45 (fee schedule change), CO-97 bundling edits, or coverage CARCs tied to an LCD or NCD. Unlike codes that name a missing field, M16 pairs promiscuously — the CARC defines the problem, M16 just cites the paperwork. Translate combinations with the denial code lookup.
What should you do when you see M16?
- Work the CARC on its own merits — appeal, correct, or write off per that code.
- Locate the referenced policy in the payer portal or MAC site and save a copy with the claim.
- If the policy is new, check its effective date against your date of service; retroactive application is appealable.
- Update your scrubber or charge rules so the rest of the schedule does not hit the same edit.
How do you prevent M16 surprises?
You cannot prevent the code itself — it is informational — but you can stop being surprised by it. Assign someone to skim provider bulletins from your top five payers monthly, and route M16 clusters to that person. A practice that reads the bulletin in March avoids the six weeks of denials in April. Trend M16 by CPT code; two or more in a week on the same code means a policy moved.
Frequently asked questions
Not by itself. M16 is an Alert remark; the denial or reduction, if any, is carried by the CARC on the same line. M16 just tells you the payer has published the reasoning somewhere — a medical policy, a fee schedule update, a provider bulletin. Read the CARC first, then go find the document.
Start in the payer portal under medical policies or provider news, searching by the CPT code on the denied line. For Medicare, check the MAC website and any recent LCD or article revisions. If you cannot locate it in ten minutes, call provider services and ask for the specific policy number that drove the adjustment — reps can see it.
That is the classic M16 pattern: a policy changed. Payers use M16 to flag lines affected by a new edit, a coverage revision, or a fee schedule update. Treat a cluster of M16s on one CPT as an early warning to pull the new policy before the denials pile up.
Sources & further reading
Reviewed by the ImmediCare Solutions RCM team
Certified billers and coders handling claims across 50+ specialties nationwide. This entry is reviewed against current payer policy and CMS rules. Last review: Jul 5, 2026.
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