Last Updated on September 11, 2025
Medicare crossover claims are a streamlined process that helps providers receive timely, accurate payments when patients have both Medicare and secondary insurance coverage. After Medicare adjudicates its portion, the claim details are automatically forwarded to the secondary payer, reducing duplicate submissions and minimizing patient billing errors.
Still, many billing teams encounter confusion when crossover claims don’t process as expected or when remittance codes are unclear. Understanding how the crossover process works, including the forms required and the codes that confirm success, can help providers strengthen revenue cycle performance and stay compliant with payer rules.
This guide breaks down the Medicare crossover claims process in detail, offering both technical insight and practical strategies to simplify billing workflows.
Table of contents
What Are Medicare Crossover Claims?
A Medicare crossover claim is a claim that Medicare automatically forwards to a patient’s secondary insurance once it has processed and paid its portion. This process eliminates the need for providers to bill the secondary payer separately.
Secondary insurance could be Medicaid (for dual-eligible patients), a Medigap plan, or even a commercial policy. The forwarding of claims is facilitated by the Coordination of Benefits Agreement (COBA) administered through CMS’s Benefits Coordination & Recovery Center
By design, crossover claims reduce administrative burden and protect patients from being billed for amounts their secondary coverage should handle. Without crossover, providers often find themselves resubmitting claims, posting secondary payments manually, and facing revenue leakage from unpaid balances.
How Do Medicare Crossover Claims Work?
The crossover process can be broken down into four distinct stages:
Step 1 – Medicare as the Primary Payer
When a provider submits a claim to Medicare, it processes the claim and pays its portion based on the Medicare fee schedule.
Step 2 – Automatic Forwarding via COBA
Through the COBA process, Medicare electronically forwards the claim data to the secondary payer. Each secondary payer has its own COBA agreement, which determines how claims are routed.
Step 3 – Secondary Payer Adjudication
The secondary insurer reviews the forwarded claim and pays what remains, such as deductibles, coinsurance, or co-payments, according to the patient’s coverage.
Step 4 – Remittance Advice Indicators
Providers should carefully review their Medicare Remittance Advice (RA). Remark codes like MA18 (“claim information forwarded to additional payer(s)”) and N89 (“information forwarded to another payer from Medicare”) confirm that a claim has crossed over
If these codes do not appear, the claim did not cross over and must be submitted manually.
Practical tip: Not all claims are eligible for crossover. Some secondary insurers may not participate in COBA or may require specific identifiers on the claim. Billing staff should maintain an updated payer list to avoid missed opportunities.
Billing Medicare Crossover Claims
While Medicare handles the forwarding, providers must still submit clean, accurate claims with correct information to ensure smooth crossover.
Eligibility and Coordination of Benefits
- Verify that Medicare is the primary payer.
- Confirm the patient’s secondary coverage through eligibility verification tools.
- Mismatched or outdated coverage details are a leading cause of failed crossovers.
Claim Forms and Data Requirements
- CMS-1500 (Form 837P) for professional services.
- UB-04 (Form 837I) for institutional claims.
- Required fields include the patient’s Medicare ID, secondary insurance ID, and payer sequence indicators.
Common Claim Codes for Crossover Claims
- MA18 – Claim forwarded to additional payer(s).
- N89 – Information forwarded from Medicare to another payer.
- COB claim adjustment reason codes (CARCs) – Used to explain how Medicare processed the claim before sending it to the secondary.
Handling Failed Crossovers
Even with COBA in place, not all claims cross over successfully. Common issues include:
- Secondary coverage not on file with Medicare.
- Patient’s eligibility changed mid-year.
- Payer identifiers missing from the claim.
When this happens, providers must bill the secondary manually, attaching the Medicare RA as proof of primary payment.
Our denial management services team helps resolve failed crossover claims and prevent recurring issues.
Why Medicare Crossover Claims Matter for Providers
Crossover claims may sound like a minor billing detail, but they have a significant impact on a provider’s financial health.
- Faster Payments and Reduced AR – By eliminating the need for manual resubmission, crossover claims shorten the payment cycle. This reduces aging AR and improves cash flow predictability.
- Lower Administrative Burden – Billing staff no longer need to chase secondary payers for balances Medicare has already adjudicated. This frees up resources for more complex claim work.
- Fewer Patient Billing Errors – When crossovers fail, patients may receive incorrect statements showing balances their secondary insurance should have paid. Proper crossover prevents these frustrating situations, improving patient trust.
- Compliance and Audit Protection – Accurate crossover handling ensures providers remain compliant with Medicare secondary payer rules. Since crossover claims are transmitted electronically, they also create a clear audit trail for compliance teams.
Medicare crossover claims simplify one of the most time-consuming aspects of billing, secondary claim management. They protect revenue, reduce administrative burden, and ensure patients are not overbilled. However, practices must remain vigilant: failed crossovers can still create denials, payment delays, and compliance risks if not monitored.
Providers that invest in eligibility verification, payer ID accuracy, and claim review processes see the greatest benefit. For many practices, partnering with a billing partner experienced in crossover claim management is the fastest path to improved collections.
Are Medicare Cross over Claims draining revenue?
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FAQs on Medicare Crossover Claims
Not every secondary payer participates in the Medicare Coordination of Benefits Agreement (COBA) program. While Medicaid and most Medigap plans receive crossover claims automatically, some commercial insurers require providers to submit secondary claims manually. Always verify whether a payer is set up for crossover.
Typically, once Medicare pays its portion, the crossover claim is sent to the secondary insurer within 24–48 hours. However, secondary payer processing times vary. Billing teams should monitor remittance advice codes and payer portals to confirm payment posting.
Yes. Providers can track crossover status through the Medicare Remittance Advice (RA), which lists specific crossover claim codes (e.g., MA18, N89). In addition, some payers provide online portals where providers can confirm that the secondary payment is in process.
Failures often happen due to outdated secondary insurance information, missing payer IDs, or changes in patient eligibility. Another common issue is when the secondary payer is not linked in Medicare’s system under COBA, which prevents automatic forwarding.
Yes. Since crossovers involve two payers, both Medicare and the secondary insurer may review the claim for compliance. Accurate claim coding, eligibility verification, and coordination of benefits documentation are critical to avoid denials during audits.
