RARC M117: Not Covered Unless Submitted via Electronic Claim
RARC M117 means the claim is not covered unless submitted electronically. Medicare requires electronic submission under ASCA for nearly all providers, and paper claims from non-exempt practices are denied with this remark. The fix is resubmitting the same claim through your clearinghouse as an 837.
- Type
- Informational (supplemental)
- Usually paired with
- CO-16, CO-96
- Fixable?
- Yes — resubmit electronically
- Typical fix
- Send the claim as an 837 through a clearinghouse
What does remark code M117 mean?
Official X12 text: "Not covered unless submitted via electronic claim." Under the Administrative Simplification Compliance Act, Medicare requires nearly all providers to bill electronically; paper claims from non-exempt providers are not just delayed, they are denied. Commercial payers with electronic-only policies use the same remark.
ERA mini-example: a practice mails a CMS-1500 for a $410.00 procedure because someone wanted to staple an op note to it. Six weeks later it denies with M117 and $0.00 paid. Resubmitted as an 837 with a PWK attachment indicator, it pays in 14 days — after losing two months of cash flow to a stamp.
Which denial code does M117 come with?
Typically CO-16 (submission error) or CO-96 (non-covered as billed). Either way the group code is CO — this is never patient responsibility, and there is nothing to appeal. The submission channel was the defect. Confirm what your specific remit pair means in the denial code lookup.
How do you fix an M117 denial?
- Resubmit the identical claim electronically through your clearinghouse — no corrections needed unless something else was wrong.
- If documentation drove the paper detour, use the electronic attachment method the payer supports (PWK segment, portal upload, or fax-on-request).
- Check the date of service against timely filing; escalate anything aged past half the limit.
- Find and close the workflow that routed the claim to paper.
How do you prevent M117?
Make electronic submission the only path: complete EDI enrollment for every payer at credentialing, monitor the clearinghouse for claims dropping to paper, and train staff that attachments ride electronically, not by mail. A monthly report of claims submitted on paper should read zero for a non-exempt practice — every entry on it is a future M117 and a month of lost cash-flow. New-provider onboarding is the moment to check: EDI gaps there generate the majority of these denials.
Frequently asked questions
Only narrow ASCA exceptions: practices with fewer than 10 full-time-equivalent employees (for Part B, small-provider definitions apply), providers with no electronic capability due to disruptions, certain claim types like some secondary or demand claims, and situations where CMS instructions require paper. Everyone else gets M117 when a CMS-1500 arrives by mail.
No. The 12-month Medicare timely filing clock runs from the date of service regardless of how many submission attempts failed. A denied paper claim does not protect the date. Resubmit electronically as soon as the M117 posts, and treat aged dates of service as urgent.
Usually an attachment or a system exception: claims needing documentation, corrected claims someone believed had to mail, or a new provider whose EDI enrollment was incomplete so the system dropped claims to paper. Find the routing reason — the M117 is a symptom of a workflow detour, and the detour will keep producing them.
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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