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Claims coordination and review

Quick payment with coordination of benefits

Quick payment with coordination of benefits

Coordination of benefits (COB) occurs when a patient is covered under more than one insurance plan. This process lets your patients get the benefits they are entitled to. It helps determine which company is primarily responsible for payment. It also helps avoid overpayment by either plan and gets you paid as quickly as possible.


When a patient comes to you, you can submit an eligibility and benefits inquiry. We will inform you if the patient is covered and which plan is primary.


Log in to submit an electronic COB claim


  • Commercial insurance claims in which another payer is primary and Aetna is secondary
  • Medicare primary claims for which Medicare* has not already forwarded their claims and payment information to us

When Aetna is secondary, you will need to include the appropriate code on your claim that tells us information about the primary payer’s payment.


Contact the practice management support team and/or the clearinghouse you use to submit your electronic claims. They may have their own guidelines or tips about submitting COB claims.


Use one of our vendors to submit COB claims


Submit claims through Availity


* We can accept both Medicare Part A and Part B claims electronically from Medicare. If the Medicare electronic remittance advice (ERA) or Explanation of Payment (EOP) contains an "MA 18" or "N89" remark code, the Medicare carrier has automatically sent us your claim. In these cases, you don't have to send us a Medicare primary COB claim.


We participate in COB Smart™, a Council for Affordable Quality Healthcare® solution.


Visit the CAQH website for more information on COB Smart


If you share our COB form with your patients, it will help you collect the data you need.


Patient COB form (PDF)


Related links


Legal notices

Aetna is the brand name used for products and services provided by one or more of the Aetna group of companies, including Aetna Life Insurance Company and its affiliates (Aetna).


Health benefits and health insurance plans contain exclusions and limitations.


See all legal notices

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