What is MA63 Remark Code? A Simple Guide for Medical Billers

The MA63 remark code frequently appears on claim denials, causing significant disruptions in healthcare revenue cycles. When medical billers encounter this code, it signals a missing, incomplete, or invalid principal diagnosis on the submitted claim. This critical error prevents proper processing and ultimately delays reimbursement.

Understanding the MA63 remark code description is essential for efficient claim management. Denial remark code MA63 typically occurs due to several factors, including clerical errors during data entry and inadequate documentation. Additionally, discrepancies between medical records and reported diagnoses can trigger this denial. Medical billers must ensure that the correct ICD-10 codes are paired with appropriate CPT codes to avoid such rejections. Furthermore, implementing preventive measures like staff training and pre-submission review processes can significantly reduce MA63 denials.

What is MA63 Remark Code and Why It Matters

Remark codes serve as communication tools between payers and providers in healthcare billing. The MA63 remark code indicates a problem with the principal diagnosis on a submitted claim.

Definition of MA63 denial remark code

The MA63 remark code stands for "Missing/incomplete/invalid principal diagnosis". This code appears when the primary diagnosis information on a claim is either absent, insufficiently detailed, or does not conform to required standards. Unlike some billing errors, MA63 specifically targets the foundation of medical claims—the principal diagnosis that justifies all subsequent treatments and procedures.

Principal diagnosis issues flagged by MA63 can take several forms:

• Complete absence of any diagnosis code
• Use of unacceptable principal diagnosis per ICD-10-CM guidelines
• Submission of a secondary diagnosis code as the primary diagnosis
• Inclusion of conflicting diagnosis codes (such as right vs. unspecified limb)
• Use of diagnoses with Excludes1 notations that cannot be billed together

How does it affect claim processing

When a claim receives an MA63 code, it essentially halts in the processing pipeline. The payer cannot properly evaluate medical necessity without a valid principal diagnosis, consequently preventing reimbursement. This code typically appears alongside Claim Adjustment Reason Code (CARC) CO16, which broadly indicates "claim/service lacks information".

The impact extends beyond simple delays. Claims with MA63 require manual intervention, often necessitating:

1. Thorough review of patient medical records
2. Communication with healthcare providers for clarification
3. Claim correction and resubmission
4. Additional administrative work tracking denied claims

Each step consumes valuable time and resources, creating financial strain on healthcare organizations. In essence, MA63 denials interrupt cash flow and increase administrative burden.

Difference between MA63 and other denial codes

MA63 belongs to the Medicare Remittance Advice Remark Codes (RARCs) category, which provides specific information about claim adjustments. Unlike general denial codes, MA63 pinpoints the exact reason for rejection—principal diagnosis issues.

In contrast to MA63, other common diagnosis-related codes target different aspects of the claim. For instance, while MA63 specifically addresses principal diagnosis problems, other codes might focus on diagnosis-procedure mismatches or medical necessity issues based on the provided diagnosis.

The specificity of MA63 makes it particularly actionable. Rather than indicating a broad problem, it directs billers exactly where to look—the principal diagnosis field. This contrasts with codes that might require more investigative work to identify the precise issue. The resolution pathway for MA63 is relatively straightforward: correct the principal diagnosis information and resubmit the claim.

Top Reasons for MA63 Denials in Medical Billing

Medical billers encounter MA63 denials for various reasons, all centered around problems with the principal diagnosis. Understanding these common causes helps organizations implement targeted solutions to prevent revenue disruptions.

Clerical errors and missing diagnoses

Data entry mistakes account for the vast majority of claim rejections, with studies showing 90%-93% of denials stem from preventable errors. Simple clerical oversights often trigger the MA63 remark code when staff incorrectly enter or completely omit the principal diagnosis. These errors manifest in several ways:

• Missing primary diagnosis codes (code 20157)
• Absence of admitting diagnosis (code 1917)
• Transposed numbers in diagnosis codes
• Misspelled information that fails to match medical records

Outdated or incorrect ICD-10 codes

The transition to ICD-10 introduced significantly greater specificity requirements, causing many practices to see increased MA63 denials. Many rejections stem from:

• Using discontinued or invalid diagnosis codes
• Submitting codes that don't reflect the latest coding standards
• Failing to meet the specificity requirements of ICD-10
• Using admitting diagnosis codes that payers consider invalid (code 20164)

EHR system issues and software glitches

Technology plays a crucial role in modern medical billing, yet it can also contribute to denial problems. Software or electronic health record (EHR) system errors frequently result in the omission or misreporting of principal diagnoses. These technical issues include:

• Diagnosis fields are not properly mapped in claim generation
• System updates that alter coding requirements without notice
• Software that fails to flag missing principal diagnoses
• Interface problems between clinical and billing systems

Lack of provider-coder communication

Miscommunication between healthcare providers and coding staff represents another significant factor in MA63 denials. This breakdown typically involves:

• Incorrect interpretation of the principal diagnosis due to poor documentation
• Inadequate training for coding personnel on diagnosis selection
• Insufficient updates about changing coding guidelines
• Limited feedback loops between providers and billing departments

Addressing these root causes requires a systematic approach to claim submission processes and ongoing staff education.

How to Fix and Resubmit Claims Denied with MA63

Receiving an MA63 denial isn't the end of the road—it's a fixable problem with a clear pathway to resolution. Once identified, medical billers can systematically address these denials through proper procedures.

Step-by-step review of the claim

First and foremost, a comprehensive review of the denied claim is essential for identifying the exact principal diagnosis issue. The process should include:

1. Examining the remittance advice to confirm the MA63 code
2. Reviewing additional remark codes that accompany MA63 for specific guidance
3. Checking for common diagnosis issues like modifier mismatches (e.g., RT modifier with LT diagnosis)
4. Identifying if the claim contains unacceptable principal diagnoses per ICD-10-CM guidelines

Notably, payers will utilize multiple descriptive remit codes that provide specific clues about what's missing or incorrect.

Verifying and updating the principal diagnosis

After examining the claim details, medical billers must verify the diagnosis documentation:

• Check if the principal diagnosis is completely absent from the claim
• Determine if the diagnosis code meets specificity requirements
• Identify cases where secondary diagnoses were incorrectly listed as primary
• Look for Excludes1 diagnoses that cannot be billed together

In the event that a diagnosis is incomplete or invalid, medical billers should clarify any ambiguities with the provider and ensure coding reaches maximum specificity.

Communicating with the treating provider

When diagnosis information is missing or unclear, reaching out to the healthcare provider is crucial. This communication should:

• Be specific about what information is needed
• Reference the exact patient and service date
• Request clear documentation of the principal diagnosis
• Obtain necessary information to support proper coding

Above all, maintain detailed records of these communications for future reference.

Using the correct CPT and ICD-10 codes

Before resubmission, ensure all coding elements are correct:

• Update the principal diagnosis code based on provider feedback
• Review the claim for any "Excludes1" diagnoses that cannot be billed together
• Add the appropriate primary diagnosis when the secondary diagnosis is the only one on the claim
• Consider common diagnosis denials like sequela codes (S06.2X9S) or manifestation codes incorrectly used as principal diagnoses

Once corrected, resubmit the claim promptly, as unprocessable claims require new submissions rather than appeals.

Best Practices to Prevent Future MA63 Denials

Preventing MA63 remark code denials requires a proactive approach rather than just reactive fixes. Healthcare organizations can implement several strategies to minimize these diagnosis-related rejections before claims even leave the office.

Training staff on documentation accuracy

First and foremost, invest in comprehensive training programs focused on documentation precision. Studies show that 90%-93% of claim rejections stem from preventable data entry mistakes. Staff education should emphasize:

• Verification of all insurance and demographic information before and during patient appointments
• Proper capture of principal diagnosis codes
• Understanding the relationship between diagnosis documentation and claim payment

Medical billing teams should be trained to scrutinize Explanation of Benefits (EOB) documents thoroughly, as they contain valuable information about denial reasons.

Using EHR alerts for missing diagnoses

Electronic health record systems offer powerful prevention tools against MA63 denials. Modern EHR platforms can incorporate built-in prompts and alerts that flag missing or incomplete diagnosis information before claim submission. These automated safeguards catch potential issues when providers might forget to document the principal diagnosis, effectively stopping problems before they affect reimbursement.

Regular audits and feedback loops

Ongoing monitoring remains crucial for preventing diagnosis-related denials. Healthcare organizations should track and trend remark codes like MA63 over time to identify systemic vulnerabilities. Weekly and monthly reports organized by carrier help pinpoint specific problem areas. Moreover, implementing a pre-claim submission review process allows teams to catch and correct principal diagnosis errors before they result in denials.

Staying updated with coding guidelines

ICD-10 guidelines undergo regular updates that directly impact diagnosis coding. For instance, significant changes to COVID-19 coding guidelines became effective April 1, 2025. Therefore, medical billing professionals must maintain current knowledge of coding standards. This involves regular review of official coding guidelines and ensuring all staff members receive timely updates about changes that could affect principal diagnosis selection and documentation.

Conclusion

Understanding the MA63 remark code remains essential for healthcare organizations aiming to maintain smooth revenue cycles. Throughout this guide, we have explored how this specific denial code identifies problems with principal diagnoses, significantly impacting claim processing and reimbursement. Certainly, MA63 denials create administrative burdens, yet they also present opportunities for process improvement.

Medical billing teams must recognize that most MA63 denials stem from preventable issues. Therefore, addressing clerical errors, outdated coding practices, EHR system glitches, and provider-coder communication gaps should become priority areas for improvement. Despite their disruptive nature, these denials can be systematically resolved through proper claim review, diagnosis verification, provider communication, and accurate code selection.

Prevention ultimately proves more valuable than correction. Healthcare organizations that implement comprehensive staff training programs, utilize EHR alerts, conduct regular audits, and stay current with coding guidelines experience fewer MA63 denials. Consequently, these practices lead to faster reimbursements and reduced administrative workloads.

Medical billers who master the management of MA63 denials position their organizations for financial stability and operational efficiency. After all, each properly coded principal diagnosis represents not just compliance with technical requirements but also accurate clinical information that justifies treatment and ensures appropriate reimbursement. The strategies outlined in this guide provide a roadmap for effectively handling these common yet manageable denials.

FAQs

Q1. What does the MA63 remark code signify in medical billing? 

The MA63 remark code indicates that there is a missing, incomplete, or invalid principal diagnosis on a submitted medical claim. This code is used when the primary diagnosis information doesn't meet the required standards or is absent altogether.

Q2. How does an MA63 denial affect claim processing? 

An MA63 denial halts the claim processing pipeline, preventing proper evaluation of medical necessity and reimbursement. It requires manual intervention, including review of medical records, communication with healthcare providers, and claim correction and resubmission.

Q3. What are the common reasons for receiving an MA63 denial? 

Common reasons for MA63 denials include clerical errors during data entry, use of outdated or incorrect ICD-10 codes, EHR system issues or software glitches, and lack of communication between healthcare providers and coding staff.

Q4. How can medical billers fix claims denied with MA63? 

To fix MA63 denials, medical billers should review the claim thoroughly, verify and update the principal diagnosis, communicate with the treating provider for clarification if needed, and ensure the use of correct CPT and ICD-10 codes before resubmitting the claim.

Q5. What best practices can prevent future MA63 denials? 

To prevent MA63 denials, healthcare organizations should focus on training staff in documentation accuracy, using EHR alerts for missing diagnoses, conducting regular audits, implementing feedback loops, and staying updated with the latest coding guidelines.