RARC MA04: Primary Payer Information Missing for Secondary Claim

What Does RARC MA04 Mean?

MA04 surfaces when a claim is submitted to a secondary payer but lacks the information needed to coordinate benefits with the primary payer. In a dual-coverage scenario, the secondary payer needs to know what the primary payer paid, denied, or left as patient responsibility before it can calculate its own payment. Without this data, the secondary payer has no basis for adjudication and will hold or deny the claim.

The most common trigger is simply omitting the primary payer's Explanation of Benefits (EOB) or electronic remittance data when submitting the secondary claim. This can happen when the primary payer's remittance has not yet arrived, when the crossover process between payers fails, or when the billing staff submits to the secondary payer before confirming the primary's adjudication. In electronic billing, the coordination of benefits (COB) segments of the 837 claim must be populated with the primary payer's adjudication details — if these fields are empty or contain placeholder values, MA04 will result.

MA04 is typically paired with CARC 22 (payment adjusted based on coordination of benefits) or CARC 16 (missing information). When Medicare is the secondary payer, claims may cross over automatically from the primary, but if the automatic crossover fails or the primary payer is not set up for electronic COB, the provider must manually submit the claim with primary payment details attached.

What to Do

Obtain the primary payer's EOB or electronic remittance for the claim in question. Verify the primary payer's adjudication details: what was paid, what was applied to the patient's deductible or coinsurance, and what was denied. Enter this information into the COB fields of the secondary claim — on paper claims this goes in the appropriate fields on the CMS-1500 or UB-04, and for electronic claims it populates the 837 COB loop. Resubmit to the secondary payer with complete primary payment data.

If the primary payer's remittance is delayed, follow up with the primary payer to expedite processing before the secondary payer's filing deadline passes. For practices that frequently bill secondary claims, establishing a workflow that holds secondary submissions until primary adjudication is confirmed can eliminate most MA04 denials. Also verify that automatic crossover agreements are functioning properly — a breakdown in the crossover process can generate a wave of MA04 denials across your entire secondary claim volume.

Common Scenarios

• A patient has both employer-sponsored insurance and Medicare, but the billing office submits to Medicare (secondary) before the primary insurer has processed the claim, resulting in MA04.
• The automatic crossover between a Medicare Advantage plan (primary) and Medicaid (secondary) fails for a batch of claims, and each one returns with MA04 because the secondary payer received no primary adjudication data.
• A billing specialist enters the secondary claim manually but forgets to populate the primary payer's payment amount and adjustment reason fields, leaving the COB section incomplete.

Commonly Paired With

RARC MA04 commonly appears alongside these CARC denial codes: