Coordination of Benefits is a process through which individuals/families with access to more than one insurance plan and/or drug benefit program sequentially submit their claims to their insurers. The portion of the drug cost not paid for by the first insurer is claimed through the second insurer.
To decide which insurer should be used first, one has to refer to the individual insurance plan/drug program policies. Plans characterizing themselves as secondary payers or payers of last resort will inform you of which types of insurance you need to access (if you have that type of insurance) before you put a claim through them. See the individual provincial/territorial and federal drug programs in this Website for their specific requirements. If you have private insurance, call the insurance company to find out the rules that apply to your particular plan (you will need your benefits policy number and employer's name when you call the insurance company).
By claiming drug costs that are not covered by one insurer through the second insurer, beneficiaries can minimize or eliminate their out-of-pocket costs. Also there may be instances where your primary insurer does not cover a specific medication but the secondary payer will.
If you have prescription drug insurance through more than one plan/program, you may be able to claim any copay you were required to pay through the first plan, to the second plan.