Coordination of Benefits

Modified on Thu, 19 Feb at 7:40 PM

Summary

Many providers ask how secondary billing works. This article explains how primary and secondary insurance process claims, what Zaya supports, and what to do in each scenario.

How Primary and Secondary Insurance Works

When a patient has two insurance plans, such as an employer-sponsored plan and coverage through a spouse, claims are processed in a specific order.

The primary insurance always processes the claim first.

Example:

Office visit charge: $200
Primary allowed amount: $160
Patient responsibility: $40 (copay, coinsurance, or deductible)

After the primary processes the claim, it moves to the secondary insurance.

The secondary payer:

Reviews what the primary allowed and paid
Determines whether to cover all or part of the remaining patient responsibility
Applies its own coordination of benefits (COB) rules

The secondary insurance will not process the claim until the primary has completed processing, even if the primary denies the claim.

Secondary payment is not guaranteed. Each payer applies its own coverage rules.

Importance of an Eligibility Check

Before submitting a claim to Zaya, verify eligibility for both primary and secondary coverage.

Running an eligibility check helps you:

Confirm which plan is primary
Identify coordination of benefits issues
Prevent avoidable denials or delays

Incorrect COB setup is a common cause of payment delays.

Refer to our article on which plans Zaya covers for a complete list of supported payers.

How Zaya Handles COB and Secondary Billing

We currently DO NOT support secondary billing within our system.

If a patient has secondary insurance that is not in network with Zaya, you must handle both steps directly:

Submit the primary claim through your own billing system using your Tax ID and NPI.
After the primary claim processes, submit the secondary claim through your own billing system.

Secondary claims must be submitted by the same billing entity (same Tax ID and NPI) that submitted the primary claim.

Table 1: Before Claim Submission

Scenario	Primary Insurance	Secondary Insurance	Can Zaya Accept the Claim?	Notes / Required Action
Patient has only one active primary insurance within Zaya network	✅ In-network	❌ None	✅ Yes	Proceed with standard claim submission.
Patient has primary and secondary insurance, both in Zaya network	✅ In-network	✅ In-network	⚠️ Partial	Zaya can process the primary claim only. Secondary billing is not supported.
Patient has primary insurance outside Zaya network and secondary within	❌ Out-of-Network	✅ In-network	❌ No	Zaya cannot accept because primary must be billed first.
Patient has secondary-only coverage (no active primary on file)	❌ None	✅ In-network	❌ No	Zaya cannot submit secondary-only claims.
Patient has missing or unclear COB information	⚠️ Unknown	⚠️ Unknown	⚠️ Hold	Verify insurance hierarchy (primary vs. secondary) before submission.

Table 2: After Claim Submission (COB or Denial Scenarios)

Scenario	Denial Reason / Status	Can Zaya Resubmit or Bill Secondary?	Notes
Claim denies for COB and patient has another primary within Zaya network	COB / Other primary not billed	✅ Yes, resubmit with correct primary info	Zaya will not bill the secondary.
Claim denies for COB and patient's primary is outside Zaya network	COB / Out-of-network primary	❌ No	Zaya cannot process out-of-network primaries; patient or external biller must handle.
Claim processed by primary, and patient has secondary coverage	Primary EOB received	❌ No	Zaya will not submit to secondary. The patient can submit a member reimbursement to secondary plan