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Coordination of Benefits (COB)


Coordination of Benefits (COB) provisions allow health plans to coordinate their reimbursements for services provided to a patient. Medica will coordinate reimbursement with another Medica benefit plan or a non-Medica benefit plan or health insurance policy.

When reimbursements are coordinated, combined reimbursements from the various carriers will be limited to 100% of allowable charges. This is designed to eliminate overinsurance or duplication of benefits.

Please notify Medica when a member has multiple insurance coverage by:
  • Indicating a primary carrier on the CMS-1500 (formerly HCFA-1500) claim form (box #9a-d). 
  • Indicating a primary carrier on the UB-04 claim form (boxes 52, 53, 54 and 55) and value codes.
  • Having the member notify Member Service if there is a primary carrier and Medica is secondary.

Download CMS-1500 (formerly HCFA-1500) claim form.
Downlaod UB-04 claim form.

COB is designed to protect members and their employers from higher premiums that result when duplicate reimbursements are made by two insurance companies. COB allows for reimbursement of up to 100% of allowable charges, which means that out-of-pocket expenses (copayments, coinsurance and deductibles) are minimized or eliminated.


What Happens When Medica Receives a Claim?

If Medica has not investigated for COB in the past or if Medica has information that is more than 365 days old, then the claim will be denied “member liability” with denial code 603 and a fresh COB questionnaire will be sent to the member. After the member responds to the questionnaire, the COB edit will be set up in the system. When the member responds to the questionnaire, the provider will be notified with adjustment code 056, “member COB verification received.” If Medica is determined to be primary, the claim will reprocess overnight. The provider will not be required to take any further action on this claim. If Medica is deemed to be secondary, the claim will be denied “provider liability” with the 047, “send primary carrier’s EOB”, denial code as it is today.

Medica follows the National Association of Insurance Commissioners (NAIC) COB guidelines in determining primary and secondary payers.


Coordination of Claims

The primary health plan reimburses up to its benefit limit, as it would in the absence of another insurance carrier. The secondary plan reimburses the difference between the primary insurer’s benefits and the total incurred allowable expenses up to its limits.

When Medica is Primary Carrier.

When Medica is Secondary Carrier.

Determination of Primary Carrier.


COB Calculations

There are two methods for calculating COB benefits. Alternative One is the central focus of the NAIC guidelines. Alternative Three is used by some self-insured groups. (Alternative Two was a combination of Alternatives One and Three, but is no longer used.)

Alternative One

Alternative Three



Coordinating Benefits with Medicare

A participating provider who “accepts Medicare’s assignment” agrees to the amount that Medicare allows for a particular procedure. Although the member may have a Medicare copayment, coinsurance or deductible to meet for the service(s), the difference between the billed charge and the allowed amount will not be billed to the patient.

If the provider “does not accept assignment:”

Medica coordination with Medicare for assigned claims:

Medica coordination with Medicare for unassigned claims:


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