Billing Secondary & Tertiary Claims

Most health plans are written so that plan members share in the cost of healthcare. 

For example, an 80/20 plan means that a carrier will pay 80% of the covered charges leaving the patient to pay the remaining 20%.

Some patients have access to a second or even a third (tertiary) health plan that helps to offset some of the patient's share of costs.

This additional coverage may be available because:

  •  A spouse also has health coverage through their employer
  •  A patient has two jobs and two plans
  •  Two working parents each insure a child under an employer plan
  •  Government plans like Medicare or Medicaid
  •  Medicare Medigap plans
  •  Military plans

When a patient has more than one plan, all health plans will be billed and all payments will be applied to that date of service. In spite of how the clam is calculated no more than 100% of the billed charge will be paid.

The process for billing more than one carrier

  • The health carrier deemed to be the primary carrier is billed first. Refer to the section entitled COB to learn more about how to determine who pays first when you have more than one plan.
  •  Both carriers CANNOT be billed at the same time. The primary carrier is billed first and once they process the claim, the secondary plan is billed and so on.
  • The primary carrier will determine their liability and the EOB from this determination is used to bill the secondary carrier. Unless you have a way to attached the EOB electronically, your secondary claim will be billed as a paper claim.
  • The secondary carrier will use the primary carrier's EOB to determine their liability.

Example of primary/secondary processing

Ben J. has an 80/20 plan through his place of employment and his wife, Janis J, also covers him under an 80/20 plan through her company. Neither plan has a deductible.

Ben goes to the doctor and incurs $500.00 in healthcare costs.


The same claim is billed to Janis’ plan with the EOB showing the $400.00 payment.

Although Janis’s plan could pay out $400.00 they know (because the EOB tells all) that the bill was only $500.00 and that $400.00 has already been paid by the primary carrier - they issue a payment for $100.00

Between the two carriers the claim has been paid in full with ZERO out of pocket from the patient.

Keep in mind that secondary (tertiary) reimbursement is subject to the provisions under each plan and the allowed amounts. Depending on the processing guidelines 100% may not always be forthcoming. 


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