How do primary and secondary payers determine which plan pays first?

• A. The secondary payer pays first.
• B. The primary payer pays first; the secondary pays remaining allowed expenses per COB rules.
• C. The one with the higher premium pays first.
• D. The plan with the smallest deductible pays first.

Answer: (B)

Coordination of benefits (COB) is the rule that determines which health plan pays first when you’re covered by more than one plan. In this system, the primary plan is the one that pays first for covered expenses up to its allowed amount. After the primary has paid, the secondary plan covers any remaining eligible expenses according to its own COB rules and limits, not exceeding what it would normally pay.

This is why the correct approach is that the primary payer pays first; the secondary payer then covers any remaining eligible costs according to its COB rules. It isn’t based on which plan has the higher premium, the larger deductible, or the smallest deductible. Those factors don’t decide order—the COB determination does.

For example, if you have two plans and total eligible charges are $200, the primary plan pays its share first up to its limit. Any remaining eligible amount may be paid by the secondary plan, again up to its own limit, with you potentially responsible for any balance that remains after both plans have paid.