Two Plans — which pays first?

My son is covered by my employer’s plan, and by Medicaid.  (He qualifies for Medicaid because he has developmental delays.)  My employer’s plan has a $50 co-pay for prescriptions; Medicaid’s co-pay is $2.  When I go to the pharmacy to get drugs for him, they are always confused about what I should pay.  I think it should be the $2, but they say that my employer’s plan applies first and therefore I should pay the $50.  Who is right?

Co-Pay Conundrum

Dear Co-Pay Conundrum,

You are both right, to a point.  The pharmacy is correct that your employer’s plan pays first, but that does not mean that you pay the $50.  The Medicaid plan pays second and brings your co-pay down to the $2.  The process is called “coordination of benefits” or “C. O. B.” (pronounced See Oh Bee.)

Medicaid plans always pay after the other plans have paid.  It is the “payer of last resort” in all cases, even behind Medicare.  This means that your employer’s plan would pay for the cost of your son’s drugs minus the usual $50 co-pay.  Then, Medicaid would step in and pay the remaining cost (whatever the employer’s plan had not already paid) minus the $2 co-pay.  In your case, Medicaid will be paying $48 – the difference between your employer’s co-pay and Medicaid’s co-pay.

To straighten this out, you may need to call the Medicaid plan’s pharmacy help desk. The number should be on the back of your son’s Medicaid ID card.

Linda Riddell

About Linda Riddell

A published author and health policy analyst with 25 years’ experience, Linda Riddell's goal is to alleviate the widespread ailment of not knowing what your health plan can do for you.