Remittance advice remark code · RARC M76
Diagnosis code missing or invalid
The payer says a diagnosis on the claim is left off, incomplete or not valid. It usually appears with CARC 16, and with CARC 146 when the diagnosis wasn't valid on the date of service.
Next step: Depends on the details
Common causes
- No diagnosis is linked to the service line, or the pointer to it is wrong.
- The ICD-10-CM code is cut short and isn't coded to the full number of characters it needs.
- The code was retired or replaced in a code-set update and isn't valid for the date of service.
- The diagnosis has a typo.
How to fix it
- Check the diagnosis fields and pointers on the claim against the chart, and code to the full length the code set requires.
- Check each code against the ICD-10-CM list for the date of service.
- Send a corrected claim the way the payer requires.
- Don't add or change a diagnosis just to get paid; it has to be supported by the provider's documentation.
How long you have to appeal
| Payer | Appeal window | Timely filing | Source |
|---|---|---|---|
| Medicare (fee-for-service) | 120 days from the date you receive the initial determination, to request a redetermination from the Medicare Administrative Contractor (MAC). Medicare presumes you received it 5 days after the date on the notice. | 1 calendar year (12 months) after the date of service. Limited exceptions exist, for example when a Medicare contractor's error caused the delay. | CMS: first level of appeal (redetermination)42 CFR 424.44: time limits for filing claimschecked 2026-10-05 |
| Medicare Advantage | Non-contracted providers: 65 calendar days from the date of the plan's denial notice (remittance advice) to request a reconsideration, and you must submit a waiver of liability that holds the patient harmless. Contracted providers: use the dispute process in your plan contract.CMS counts the 65 days from the remittance notice date, which is the 60-day filing period plus the 5 days Medicare presumes it takes you to receive the notice. Some plans' own provider materials quote 60 days, so filing inside 60 days is the safer course. | Contracted providers: set by your plan contract. Non-contracted providers: CMS's appeals guidance gives no single filing limit, so check the plan's provider manual. For private fee-for-service plans, CMS applies Original Medicare's limit of 1 calendar year after the date of service. | CMS: Parts C & D appeals guidance (non-contract provider payment requests, section 40.12.1)42 CFR 422.582: standard reconsideration filing time and presumed receiptCMS Medicare Managed Care Manual, chapter 16a, section 120: PFFS timely filingUnitedHealthcare: non-contracted provider dispute and appeal rights (Medicare Advantage)checked 2026-10-05 |
| Medicaid (state and managed care) | Varies by state and by Medicaid managed-care plan. Check your state Medicaid provider manual or the plan's provider manual.Examples of the spread: New York Medicaid expects claims within 90 days of the date of service; Nevada Medicaid allows 30 calendar days from the remittance advice date to appeal a denied claim; Texas HHSC allows 120 calendar days for its medical and utilization-review appeals. | Federal rules require state Medicaid agencies to set a claim filing deadline of no more than 12 months from the date of service. Your state or plan may set a shorter one. | 42 CFR 447.45: timely claims paymentNew York Medicaid (eMedNY): general billing guidelines, professionalNevada Medicaid: tip sheet for claims appealsTexas HHSC: provider appeals, medical and utilization reviewchecked 2026-10-05 |
| Aetna (commercial) | 180 calendar days from the initial claim decision to file a level 1 reconsideration. A level 2 appeal is due within 60 calendar days of the reconsideration decision. Some states set a different window for fully insured plans; Aetna lists them on its exceptions page. | Set by your Aetna agreement. Aetna's provider manual does not publish one national claim-filing limit, and some states set their own (for example, its New York supplement says 120 days). | Aetna: disputes and appeals overviewAetna: state exceptions for the dispute and appeal processAetna: provider manual (claim disputes must meet contractual time frames)Aetna: provider manual state supplement (New York claim submission period)checked 2026-10-05 |
| Cigna (commercial) | 180 calendar days from the date of the initial payment or denial notice. If the appeal is about a payment Cigna adjusted, 180 calendar days from the last payment adjustment. | Participating providers: 90 days after the date of service. Out-of-network providers: 180 days after the date of service. Exceptions apply, such as a longer period required by law or allowed in your provider agreement. | Cigna: appeals and disputes for health care providersCigna: submit and pay claims (filing limits)checked 2026-10-05 |
| UnitedHealthcare (commercial) | 12 months from the date of the original claim EOB or remittance advice, counting the claim reconsideration step and the appeal step together (not 12 months for each). Your agreement or state law can change this. | Set by your UnitedHealthcare agreement and by state requirements. The Administrative Guide gives no single national limit, so check your Participation Agreement. | UnitedHealthcare: 2026 Care Provider Administrative Guide (claim reconsideration and appeals, timely filing)UnitedHealthcare: pre- and post-service appeals and reconsiderationschecked 2026-10-05 |
| Blue Cross Blue Shield (local plans) | Varies by local Blue plan; there is no single national window. Check the provider manual and contract for the Blue plan you bill. For out-of-area (BlueCard) patients that is usually your local plan, not the plan on the member's card.BCBS is an association of independent, locally operated companies, each with its own provider manual. | Varies by local Blue plan. | BCBSA: local Blue Cross and Blue Shield companiesHighmark: BlueCard program FAQ (claims for out-of-area members go to your local Blue plan)checked 2026-10-05 |
Your payer contract may set a different window.
Related codes
Sources
- X12 Remittance Advice Remark Codes checked 2026-10-05
This explanation is written in our own words. Check the official list for the exact code text.