Got Questions on CARCs and RARCs? You’re Not Alone!

Our Account Services team members spend their days immersed in the Independent Dispute Resolution (IDR) process and often field questions from parties – particularly around IDR remark codes. When we notice clients are asking similar questions, it points out a need for clarity that probably stretches well beyond those who emailed or called.   

Answering those questions and making the IDR process work smoothly and efficiently is our job. So, we thought sharing answers on our blog to common questions might be useful to parties engaging in the IDR process.  

To kick off our “Common Questions” series, we’ll share some recent questions and answers we’ve provided surrounding remark codes. These CARCs and RARCs are subject to new requirements under the IDR final rule published in spring 2026 and it makes sense there are questions as the rules evolve.  

Question #1: 
Does the addition of a remark code that signifies the claim is not eligible for the federal NSA process stop an IP from disputing that claim? 

• No. Although a certain remark code is applied to a claim or reimbursement, the provider may still initiate a dispute, and FHAS will perform an eligibility review. The remark code is one factor FHAS must consider along with other information associated with the claim, including additional evidence submitted by both parties. We recommend disputing the remark code directly with the health plan before submitting though as the health plan does have the ability to correct it if applied in error. 

Question #2:  
What if the remark codes on an EOB conflict, such as when one code signifies a claim is NSA eligible and another signifies it is not?  

• Our recommendation is to dispute the remark code directly with the health plan outside of the NSA process if there is disagreement with its application.  Once corrected, and if eligible, then submit the dispute to the NSA process. If the remark code is not corrected and your party still believes it is eligible, you can initiate a dispute but be sure to include evidence that will assist our team in reviewing eligibility.  

Question #3:  
If a claim or reimbursement does not contain the required remark code signifying NSA eligibility, it can sometimes take a long time to investigate if it is eligible. How do we protect the open negotiation window in the event the claim is eligible, but the timeline has passed?  

• CMS has addressed this question and advises the initiating party to email CMS to request an extension for the open negotiation period. CMS’s guidance (page 8) is summarized here:   

If a plan or issuer fails to use the required RARCs on the remittance advice, providers retain the right to initiate open negotiation within 30 days of receiving the initial payment or notice of denial of payment. If that noncompliance leaves the provider without the information needed to initiate the Federal IDR process by the deadline, the provider may request an extension for extenuating circumstances by emailing FederalIDRQuestions@cms.hhs.gov.